June 23, 2021


The immortal aquarium?

I remember an old sayings to the effect that, "...Nothing is ever wasted..."

I've often applied this adage to my aquarium work. Quite literally, actually. If you've been in the hobby for any appreciable length of time, you've no doubt heard that one of the best ways to "kick start" the biological process in a new aquarium is to add some substrate from an established, healthy aquarium.

It's hardly a new idea.

The thinking is that the established material contains a population- an inoculant- of beneficial bacteria and other microorganisms to help establish pioneering populations in your new tank.

It's a sound practice that has borne the test of time well, and is part of basic aquarium keeping. It's the thinking behind many strategies and products used to help establish the nitrogen cycle in new tanks. I've always embraced this practice, and have sort of taken it farther in the past decade or so.

Since botanical-style aquariums at their very foundation rely on biological processes and diversity, I tend to utilize more than just a handful of sand for this process. I will typically use wood, botanicals, twigs, and even some of the leaves, regardless of their condition, for this process. 

So yeah, I'll literally transfer a fair percentage of the "software" from an existing tank into the new one. The rationale is exactly the same as the rationale for using sand from an established tank. And, as you probably recall, fungal growths and bacterial biofilms are also extremely valuable as food sources for life forms at many levels, including fishes.

The growth of these organisms is powered by...decomposing leaf litter! 

And the idea of adding "pre-colonized" materials from existing tanks to help "jump start" a new tank is simply a logical and economical practice. Having a big chunk of completely-established ecology transferred from one tank to another is almost too easy a process not to take advantage of!

Now, sure, transferring all of this material over isn't a way to take a shortcut to circumvent the establishment of the nitrogen cycle in the new tank, it's a step in establishing it. A way to bring some extant ecology into a new location.

And, think about it: This isn't all that different than what happens when a stream overflows and forms a new small tributary. Some of the materials from the established aquatic ecosystem flow into the newly-inundated area, bringing with them their "on-board" population of microorganisms, fungi, and insects.

Nothing's ever wasted, right?

This isn't exactly earth-shattering, I know, but it's worth thinking about vis-a vis our aquarium work. 

And, as we've discussed many times, the same sort of concept applies when you're "remodeling" an existing aquarium; perhaps switching up from say, a "South American theme" to an "African theme", or whatever.

This is similar to the Japanese aquascaping practice of "sozo haishoku" espoused by the "Master" of this in aquariums, the late Takashi Amano. This is the processs of removing of as much old substrate material as possible along with the plants it contains in an aquarium, and replacing them with new materials.

It preserves the overall "composition" of the layout, but the "softscape" (botanicals and leaves, in our case) could change dramatically.

Yeah, in the world of the botanical-style aquarium, the idea of leaving the substrate and leaf litter/botanical "bed" intact as you "remodel" isn't exactly a crazy one. It's about preserving ecology over time, and despite changes.

And conceptually, once again, it sort of replicates what occurs in Nature, doesn't it?

Yeah, think about this for just a second.

This idea is at the very heart of the "Urban Igapo" idea we love so much!

As we almost constantly discuss, habitats like flooded forests, meadows, vernal pools, igarape, and swollen streams tend to encompass terrestrial habitats, or go through phases where they are terrestrial habitats for a good part of the year.

In these wild habitats, the leaves, branches, soils, and other botanical materials remain in place, or are added to by dynamic, seasonal processes. For the most part, the soil, branches, and a fair amount of the more "durable" seed pods and such remain present during both phases. 

Materials are utilized in the habitat continuously.

As the waters return, the formerly terrestrial physical environment is now transformed into an earthy, twisted, incredibly rich aquatic habitat, which fishes have evolved over eons to live in and utilize for food, protection, and complex, protected spawning areas. 

All of the botanical material-shrubs, grasses, fallen leaves, branches, seed pods, and such, is suddenly submerged; often, currents re-distribute the leaves and seed pods and branches into little pockets and "stands", affecting the (now underwater) "topography" of the landscape.

It's all an elaborate dance, choreographed by Nature, encompassing numerous organisms, each filling a specialized role in the burgeoning aquatic ecosystem.

Continuing, developing, and evolving cycles and processes which have gone on for eons is what Nature does best.

Nothing is ever wasted. 

I might just be torturing this simple idea to death- I admit this point that I'm probably not adding much more to the "recipe" here; likely simply being redundant and even a bit vague...However, I think we need to think about how interesting and indeed, transformative this simple practice is.

And yeah, I'll concede that we probably don't have every answer on the processes which govern this stuff.

For example:

The most common question I get when it comes to taking out a fair amount of this material and then "continuing" the tank is, "Will it cycle again?"

And the answer is...Sure, it could.

On the other hand, here is my personal experience:

Remember, I keep a sort of diary of most of my aquarium work. I have for over three decades (gulp...). Just random scanning my "diary", I see that I have executed this practice dozens of times in all types of aquariums, ranging from simple planted aquariums to hardscape-only tanks, to botanical-style, blackwater and brackish aquariums, to reef tanks.

Not once- as in never- have I personally experienced any increase in ammonia and nitrite, indicative of a new "cycle."


Now, this doesn't mean that I guarantee a perfect, "cycle-free" process for you.  I'd be a complete asshole if I asserted that! Every system is different. There are numerous factors which impact the unique functions of a specific tank.

And you can't simply expect instant results, right?

Transferring a good compliment of material to an otherwise brand-new tank isn't going to fool Nature.

On the other hand, in an existing tank, by leaving the bulk of the substrate material and botanicals intact, and continuing to provide "fuel" for the extant biotia by leaving in and adding to the botanicals present in the aquarium, this lack of a "new" cycle makes a lot of sense.


Botanical-style systems are, in my opinion, more robust than they are vulnerable.

I believe that our botanical-style systems, with their diverse and dynamic biology, rebound quickly from disruptions and changes. And I also believe that, because of our approach and it's reliance on biological processes, they establish themselves to a more "stable" state far more quickly than "typical" aquariums do.

Much like the natural systems they purport to represent!

Of course, I also have in place a mindset and (like most of you) a mastery of basic aquarium husbandry practices that assure success with this approach, and that's a huge key here. Patience, and the understanding that yeah, a tank might take a while to establish itself, even with a large influx of "old" materials...or grasping the fact that you might experience an ammonia or nitrite spike when you "reconfigure" an existing tank- and being able to "go with that"- is critical to success, IMHO.

Not needing to rush to some arbitrary "finish line" is a most liberating approach to keeping any kind of aquarium. It will not only guide your practices, it will instill in you a better understanding of the processes and occurrences which take place in Nature as well. 

If you look at an aquarium as you would a garden- an organic, living, evolving, growing entity- then the need to see the thing "finished" becomes much less important. Suddenly, much like a "road trip", the destination becomes less important than the journey.

It's about the experiences gleaned along the way. Enjoyment of the developments, the process. In the botanical-style aquarium, it's truly about a dynamic and ever-changing system.

Every stage of the aquarium's existence holds a unique fascination. 

By reusing and re-purposing existing materials and the organisms which colonize them in new iterations of your tank, or new tanks altogether, you're simply carrying on the same process which have occurred in natural aquatic systems for eons.

In essence, one could argue that this process instills a certain "immortality" into our aquariums...The botanical materials and substrate form one established aquarium can literally "bring life" to a succession of new systems indefinitely!

A sort of "immortality", for sure!

Something to think about, right?

I believe so...

Stay thoughtful. Stay patient. Stay observant. Stay diligent...

And Stay Wet.


Scott Fellman

Tannin Aquatics 





June 22, 2021


Clouds on the horizon...or in your tank?

In the aquarium hobby, we have an obsession with crystal clear water... Now, I'm not talking about water devoid of color...We have sort of reached a point where "tinted" water is accepted and even desired- a huge mental shift that many have made.

However, when it comes to clarity- that's still a "frontier" for a lot of hobbyists; perhaps even a "bridge too far" for some. That's a different "mental shift!" I wanted to return to this "clarity" idea again today, because there are some aspects of "clarity" that I think are sort of unique to the botanical-style aquarium. 

Of course, since botanical-style aquariums are conceived to operate differently in the first place, you've likely noticed that they aquariums display a number of characteristics which make them different from more "conventional" aquariums in function and appearance.

One of the things you might notice right from the start is that botanical-laden aquariums seem to have an initial "haze" or turbidity that is slow to clear. Now, part of this is no doubt due to the breakdown of the leaves, pods, etc. that we use: Surface dirt, lignin, and other compounds, bound up in the tissues of the botanicals, released into the water upon the initial submergence and after preparation of these materials.

Remember, just because the water in a botanical-influenced aquarium system is brownish, it doesn't mean that it's of low quality, or "dirty", as we're inclined to say. It simply means that tannins, humic acids, and other substances are leaching into the water, creating a characteristic color that some of us geeks find rather attractive. If you're still concerned, monitor the water quality...perform a nitrate test; look at the health of your animals. What's happening in there?

People ask me a lot if botanicals create "cloudy water" in their aquariums, and I have to give the responsible answer- yes. Of course they can!

If you place a large quantity of just about anything that can decompose in water, the potential for cloudy water caused by a bloom of bacteria exists. The reality is, if you don't add 3 pounds of botanicals to your 20 gallon tank, you're not likely to see such a bloom. It's about logic, common sense, and going slowly.

For that matter, plain old dirt and dust bound up in and on the surface tissues of many botanicals will be released, despite our best efforts at preparing them for use. Some stuff simply leaches into the water.

And the fact that many of us tend to not to use a lot of chemical filtration media in our tanks might have some impact on that, too. 

 It's also become a sort of "thing" now to use the formerly unthinkable "sedimented" substrate materials, which will, by their very composition, impart some cloudiness into the water for a few days or more after they're submerged. Because you don't rinse them like you would more traditional substrates, the cloudiness which inevitably occur is simply part of the process.

This is typically a temporary cloudiness, and will subside over time. It's not something that will forever haunt your aquarium, trust me.

And it's kind of cool, really, because it sort of replicates what occurs in natural aquatic systems upon the initial submersion of a formerly terrestrial habitat. This cloudiness is representative of a fundamental shift in how we operate our aquariums!

Another reason for this haziness is biological. 

Often, you'll experience a burst of microorganism/bacterial growth, which impacts the visual clarity as populations multiply rapidly in the "fertile" environment of a botanical system, with its wealth of organic materials supplied by the decomposing matter upon which these life forms feed.

And then there is what we call "infusoria."

One only need reflect on the classic "infusoria" cultures which every fish breeder can recall from his/her experiences- they're really cloudy! Remember, infusoria is a collective term for aquatic organisms like euglenoids, unicellular algae, ciliates, protozoa, etc.

In modern formal biological classification, the term "infusoria" is considered an antiquated, obsolete descriptor, as most of the organisms previously included in the collective term "Infusoria" are assigned to a different assemblage of taxonomic groups.

Nonetheless, it's a charming, albeit somewhat antiquated term that is still used in aquarium circles to describe the tiny organisms that arise when you soak some blanched lettuce, vegetable skin, or other plant matter in a jar of water. Or, when dried botanical materials are submerged in water!

Depending upon the density of the amount of materials and the population of the organisms in play, you could expect to see considerable cloudiness...

Now, I have placed a few drops of tank water under a microscope early in the life of several botanical-style tanks over the years, and I did see some microorganisms swimming around in there.

Of course, I am not a microbiologist, and for me to make any conclusive statements about "density" or "diversity" of the life forms I saw swimming around in my samples is a bit too amateurish! That being said, in most of these samples, I saw a fair amount of "some sort" of life forms swimming around in the water! 

Generally, I've found that the sort of "cloudiness" will typically clear after a week or two, as the "tug of war" between bacteria and "infusoria" achieves a sort of "equilibrium."

And, as mentioned above, the cloudiness could also be caused, at least in part- by the dissolving of the botanicals themselves. When you think about it, most plant parts, such as seed pods and such, are comprised of materials such as lignin, cellulose, etc., and their constituent sugars, starches, etc. And, because of this composition, will release these materials into the water column. This can happen over time, too..sort of becoming a "new normal" for your botanical-style aquarium.

Of course the idea of "cloudiness", in general, may be a "tip off" to some other issues in the aquarium. And, as we all know, cloudiness can usually be caused by a few factors:

1) Improperly cleaned substrate or decorative materials, such as driftwood, etc. (creating a "haze" of micro-sized dust particles, which float in the water column).

2) Bacterial blooms (typically caused by a heavy bioload in a system not capable of handling it. Ie; a new tank with a filter that is not fully established and a full compliment of livestock).

3) Algae blooms which can both cloud AND color the water (usually caused by excessive nutrients and too much light for a given system).

4) Poor husbandry, which results in heavy decomposition, and more bacterial blooms and biological waste affecting water clarity. This is, of course, a rather urgent matter to be attended to, as there are possible serious consequences to the life in your system.

And, curiously enough, the "remedy" for "cloudy water" in virtually every situation is similar: Water changes, use of chemical filtration media (activated carbon, etc.), reduced light (in the case of algal blooms), improved husbandry techniques (i.e.; better feeding practices and more frequent maintenance), and, perhaps most important- the passage of time.

I like the "passage of time" part best.

Now, with the "cloudiness" caused by our "technique" or application of botanicals is a slightly different story. These are sort of "natural consequences" of what we do..

Now, you could intervene in this if you wanted to...Performing larger water exchanges, employing chemical/very fine mechanical filtration media, etc. Personally, I have learned over the years NOT to let this stuff phase me. I suppose I'm so deep in my own "mindset" about letting Nature do its thing, that I don't do much to combat it...

Once this initial "microbial haze phase" passes, there are other aspects to the water clarity which will continue to emerge. And I think that these aspects are similar to what we observe in Nature.

For example, I've noticed that in many of my aquariums, particularly those with certain types of wood (like mangrove, Melastoma root, "Borneo Root", etc.), you'll get more of this "patina" to the water. Again, I'm in the realm of speculation here, but I can't help but wonder if certain wood and botanical materials/leaves have a greater content of organic materials (or more readily release these materials into the water because of their structure), lignin, tannins, etc.

One of my friends calls this "flavor", and his moniker makes sense, when you think about it!

And I think that this is a really interesting phenomenon, which is distinctive to our botanical-stye blackwater/brackish aquariums. To accept it is a choice, and it definitely requires the adoption of a mental shift to appreciate that this is very similar to what we see in many of the natural aquatic systems that we attempt to replicate.

In Nature, the accumulations of decomposing plant materials, leaves, soils, and sediments all contribute to this cloudiness or turbidity of the water. In our aquariums, it's pretty much the same.

Yes, I understand that an aquarium is NOT an open, natural system, and that there are fundamental differences between the two.

However, to see some of the processes, aesthetics, and what we call "functional analogies" (i.e.; the way materials break down, re-distribute within the tank, and how the aesthetics and water chemistry are affected by water exchanges, etc.) take place in our aquariums, we can't help but think that we're "on to something" here.

What happens in the wild often happens in the aquarium- if we let it play out.

(Image by Aquariumaniak Khizanishvili- a master of the "dirty" aquarium!)

So, yeah, our aquariums may NOT have the "crystal-clear", colorless water which many hobbyists envision when they think of what an aquarium "should" look like. Yet, with the continued, evolving work which our community is doing, we'll continue to discuss/analyze/debate the merits of such clarity profiles in our systems.

Nature- our muse and inspiration for everything we do- provides unlimited examples of elegant, healthy, well-balanced aquatic habitats which look quite contrary to what have come to expect as hobbyists over the years.

As we've discussed a lot lately, we're absolutely obsessed with the natural processes and aesthetics of decomposing materials in our aquariums. And of course, this comes with the requirement of us to accept some unique characteristics, of course!

We have taken our first tentative footsteps beyond what has long been accepted and understood in the hobby, and are starting to ask new question, make new observations, and yeah- even a few discoveries- which will evolve the aquarium hobby in the future.

So, there may be "clouds" in your tank, but defintely NOT on the hobby's "horizon!"

Stay curious. Stay observant. Stay engaged. Stay bold...

And Stay Wet.


Scott Fellman

Tannin Aquatics 



June 18, 2021


What's the problem with "realism?"

Welcome to the back of my mind.

It's a chaotic, busy, often confusing place. Sometimes, it only takes a comment or observation by a fellow hobbyist to send me into some philosophical ramblings...And today, you're going to have to suffer with me as a result of one such comment.

It got me thinking...and that's often dangerous! 😆

The other day, a fellow hobbyist was observing one of my tanks on Instagram and told me that this particular tank, and several others that I've done, are great examples, of "realism"...Now, it was a compliment, yes- and I was duly flattered. However, it also appeared to be an observation which seemed oddly "off" somehow.

I mean. "realism" is a term from the world of fine art, used to describe artworks which are painted in a realistic almost photographic way. To label an aquarium "realistic" is really an homage to its appearance...an aesthetic appraisal. Now, that's cool, but I think that every aquarium essentially is a microcosm, a little closed ecological system, and is by definition authentic...Real.

So, the "realism" part in this comment seemed to me to refer to its appearance only. An aesthetic statement...That's all good, but the most "shallow" of all appraisals, really. In a strange way, I take that type of appraisal of a tank as almost an insult! Yeah, it's in my own head, but it's like those comments about biotope contest tanks... To me, it implies that it "looks" the part, but doesn't acknowledge that it's a functional, operating ecosystem...

I mean, it makes sense- I get it. The look is what we can see easily and immediately, especially in a picture or a video. The function- which to me is the everything in the types of aquariums we play with-is more difficult to discern; you have to live with such an aquarium to understand, experience, and appreciate this aspect. 

So, that's an example of the bizarre shit in my head!

Now, in the more broad sense, let's think about a truly natural aquarium; one in which appearance is a result of the function. It's the arena that I like to play in. It's not for everyone, and it's a place where there is a lot of room for innovation. Recreating some of the function of natural ecosystems is fascinating to me.

And it creates a very difficult challenge sometimes.

Think about the idea of replicating some types of natural habitats in our aquariums...By replicating, I mean attempting to create a functional version of a specialized natural habitat. Now, there are many who will immediately dismiss this idea as complete folly, because we can't possibly recreate every aspect of an open, natural ecosystem. You know, all of the many chemical, biological, meteorological inputs which affect the formation, form, and function of a specific habitat.

I get that. However, we can recreate many of these inputs, and do so in a way that creates a functional representation of the ecosystem that we wish to portray. Of course, even that is likely down-playing some of the challenges.

Stuff like creating deep leaf litter beds in our tanks is no longer a "no go" thing in the aquarium hobby. We can actually execute them. The big "problem" that kept people from recreating functional leaf litter beds in the aquarium was the hobby mantra of not allowing organic materials to break down in our tanks for fear of "pollution." And of course, the reality is that the whole point of a leaf litter bed is to facilitate the breakdown of leaves, the sequestration of nutrients, and the colonization and reproduction of beneficial organisms (fungi, bacterial biofilms, crustaceans, etc.). 

Not only does the presence of the leaves NOT present s problem, it's a "driver" of the ecological processes that we want. In years past, the recommendation was to siphon out and remove leaves and such as they broke down, which in reality created the very dynamic of "pollution" that hobbyists were desperate to avoid in the first place!

Removing the "fuel" that drives the ecology of the system creates problems for many of the organisms which consume it, depriving them, of their food source, and leading to an incomplete "system" that will struggle to maintain good water quality.

In this case, "realism" is simply a matter of allowing the aquarium ecosystem to do what it does, with minimal intervention/interference on our part. The whole "problem" with keeping leaf litter-based aquariums is one that we as humans created, IMHO.

Leaf litter-based aquariums work.

We've also heard of the problems with attempting to recreate the functional aspects of brackish water ecosystems. Specifically, the deep, mud-and-sediment-rich substrates, decomposing mangrove leaves, and mangroves themselves. All of these things contribute to a closed aquarium ecosystem which has a large quantity of organic material present.

Again, it was a case of taking the "warnings" into account, and sort of analyzing why the hobby was telling us that we shouldn't do this. The reason, once again, was that it embraced a high level of organic materials present in the system. It required an understanding of the basics of aquarium husbandry, and the ability to observe, monitor, and maintain such an aquarium.

And above all, an understanding that the organic material present in the tank was the primary driver of the ecology. Something that I wanted- not feared.

Rich-substrate-based brackish water aquariums work. 

It's a matter of learning the 'rules of the road" and accepting that you need to manage the aquarium in perhaps a different manner than other systems you've played with before.

The idea of recreating the function and processes which occur in seasonally-inundated ecosystems, like flooded forest floors, Pantanal grasslands, and temporal pools is exciting. Replicating the wet/dry seasonal changes is a completely different approach than we've done before. The "Urban Igapo" thing.

Like so many other unusual approaches that we try in the hobby, it requires an understanding of the dynamics of the natural habitat we're trying to replicate, and considering how this can play out in a closed ecosystem.

We learned that the soils of these seasonally inundated areas are other specialized, and that they include a lot of sediment-type materials, which have not been something that we as hobbyists have cared to introduced into the aquarium before. Why? A lot of reasons...not the least of which that they cloud the water for some period of time, and may have different chemical impacts on the water. Again, these were things that we have avoided in the hobby for various reasons.

And, managing a close aquatic ecosystem through a wet and dry cycle has implications for the life forms which will reside in it. You need to monitor and be aware of the physical, chemical, and biological implications of this process. And be open to creating and perfecting new techniques.

Seasonally-inundated aquariums work.

I think the whole "realism" thought which opened this winding little discussion is something that we as hobbyists need to get our heads around. It's more than just the aesthetics. And we also need to understand that, just because trying to recreate a natural habitat requires us to face some stuff that we're not familiar with, or that we've been told is "ill advised", "difficult", or even "dangerous", doesn't make it impossible to do.

It just means that we need to get our heads around some new stuff, and not be afraid to occasionally do stuff that is contrary to aquarium hobby "best practices." NOT to "give the middle finger" to the hobby establishment and try crazy stuff just to be rebellious. Rather, it's to do our best to incorporate new ways to recreate many of the functions of Nature in the closed confines of an aquarium.

There is no problem at all with "realism" in that context!

We've got this!

Move forward.

Stay bold. Stay innovative. Stay excited. Stay studious. Stay enthusiastic...

And Stay Wet.


Scott Fellman

Tannin Aquatics 








June 17, 2021


Stuff we need to do...

Like so many of you, after many decades in the aquarium hobby, it's sometimes hard to plot my "next move"- what ideas I want to play with. I mean, sure, the hobby can be as simple as just obtaining a tank, filling it with some water, plants, rocks, and BLAM!  You have an aquarium...

On the other hand, it's supposed to be fun, and many hobbyists enjoy the process of researching, planning, sourcing. A lot of us love the idea of pushing out further and trying some completely new and exciting....Or just different. Or even, the same as what we've done before, just different.

That being said, it's always fun to try something different, isn't it? And sometimes, we could use a creative push in the right direction. I think that it's helpful to curate a little list of stuff that we need to do.

Here are a few ideas which I think we as hobbyists should play with a bit more, and the "problems" that need to be overcome when incorporating them into our hobby.

Brackish Water Aquariums

Yeah, brackish. Again. The "poster child" for misunderstood, underserved, and uninspired!

PROBLEM: It suffers from misconceptions and a void of information and examples.

Brackish water (arguably possessing a 1.005-1.010) is a sort of "middle ground" that for decades in the hobby has been well-travelled. And widely mis-understood. I've played with brackish water for almost two decades, in between reef keeping and my blackwater stuff, and in researching both the hobby work that has been done and the scientific materials out there on the wild habitats, have sort of made this conclusion that it's simply been an afterthought, at best for aquarists.

Although there is a good amount of scientific information on brackish-water habitats from which brackish water fishes come, but comparatively little hobby information out there outside of a book or article  here and there. , (with the rare exception of some biotope enthusiasts) we've sort of distilled brackish water aquarium aesthetics down to white aragonite sand, a few rocks, and maybe some hardy plants...and it's been mired in that aesthetic hell for decades.

And then there is that "perception" thing...

I think that the perception among many aquarium hobbyists was that brackish is more tricky to keep than freshwater, and easier than a reef tank, yet offers little in the way of excitement on first glance. I mean, the fish selection and availability has not been exactly stellar, with many dealers hesitant to stock brackish fishes for simple lack of demand and interest.

And quite frankly, many fishes that have been perceived to be "brackish" by hobbyists are either actually from pure freshwater habitats (I'm thinking about certain Glassfish and some Rainbows), or have some populations that are from brackish (which are seldom imported). And then there are those fishes, like Mollies. which are Euryhaline (capable of tolerating a wide range of salt concentrations), with the majority being found in pure freshwater. Salt, in many cases, is simply used for health purposes.

(P. sphenops by Hugo Torres. Used under CC by 2.5 es)

Okay, that's the problem, as I see it.

The solution, IMHO, is to bring a bit of new thinking to the equation...an approach which takes a more realistic look at how brackish water habitats really are. 

A system that embraces natural processes and functionality...And just happens to have a different aesthetic, too! Less emphasis on "sterile" white sand and crystal-clear water, and more emphasis on a functional representation of a tropical, brackish water ecosystem: Muddy, nutrient- rich, filled with mangrove leaves, and stained a bit from tannins. Beautiful in a very different, yet oddly compelling way.

Enter the age of the botanical-style brackish-water aquarium.

It's a bit different.

It's about husbandry. Management. Observation. Diligence. Challenge. Occasional failure.

Yes, you might kill some stuff, because you may not be used to managing a higher-nutrient brackish water system. You have a number of variables, ranging from the specific gravity to the bioload, to take into consideration. If you've never used salt mix before your skills will be challenged, but the lessons learned in the blackwater, botanical-style aquariums that we're more familiar with will provide you a huge "experience base" that will assist you in navigating the "tinted" brackish water, botanical-style aquarium.

It's not "ground-breaking", in that it's never, ever before been done like this before. I just don't think that t's never been embraced like this before...met head-on for what it is- what it can be, instead of how we wanted to make it (bright white sand, crystal-clear water, and a few rocks and shells...).

Rather, it's an evolution- a step forward out of the artificially-induced restraints of "this is how it's always been done"- another exploration into what the natural environment is REALLY like- and understanding, embracing and appreciating its aesthetics, functionality, and richness.  

Figuring out how to bring this into our aquariums. That sort of thing. WIth more hobbyists playing with more realistic interpretations of brackish water habitats, we'll see more discoveries, more collective experiences, more refinement of practices...and like, more breakthroughs!

Replications of the habitats of wild livebearers

Now, wild livebearers are definitely a "thing" for many hobbyists. There is something super cool about the many, many different species of fishes like Goodeids, Xiphophorus, Heterandria, etc...And even more cool is the idea of replicating their natural habitats in a more realistic manner.

PROBLEM: Finding detailed information about the wild habitats of many species is a bit difficult to come by.

Okay, again, if you scour scientific literature, you can find out some information about the habitats where these fishes occur. However, you often will only find a passing mention, or a reference to a site. It's up to you to do even more research on the specific locale and kind of go from there.

I think that replicating the natural streams, lakes, swamps, and other bodies of water in which livebearers occur naturally is an interesting endeavor! And the habitats which they come from might just surprise you.

And there are a bunch of interesting ideas and approaches you can take; Brackish, straight fresh, and...blackwater.

Yes, blackwater livebearers! 

Now, lest you get too excited that there is a super-colorful livebearer out there, which lives in blackwater and has somehow evaded the hobby and all of the famous livebearer experts for the last century, let me just burst your bubble right away, okay?

Most of these are (in no particular order):

A) grey

B) not typically found in the aquarium hobby

C) really obscure

D) did I mention, grey?

That being said, I have a few that do intrigue me for some reason.

My first target genus is Fluviphylax, which contains five described species, not one of which anyone who is not a native fisherman, lifetime member of the American Livebearer Association, or doesn't have the letters, "PhD" after his/her name has even heard of- let alone seen! These are rather interesting fishes, distinguished by really large (relative to their body size), almost "creepy-looking" eyes, the absence of a gonopodium in males, and the usual complete lack of color seemingly common to pretty much every obscure fish in the world...

(Does it get any better? Fluviphylax in all its glory! Image by Clinton and Charles Robertson, used under CC BY 2.)

Despite the creepy eyes and complete lack of anything resembling "color", they are tantalizing to me, because the genus is apparently endemic to the Amazon and Orinoco region, including habitats like lakes, swamps, and "floating meadows." Appropriately, the first species listed in the genus is Fluviphylax obscurum, which drew me in from the start- and its native range is listed as the "Upper Rio Negro basin!"  

Oh, that's interesting! Of course, that's a big geographic area, and just because it's in the "region" doesn't mean it's all decomposing leaves and dark, soupy water... That being said, some references have it listed pretty far inland, well into "blackwater country", so...

Maddeningly, no reference I could find to any type localities mentioned the specific water chemistry of the collection sites. However, one cool thing is its diet, which always makes me smile:  Its diet is described as "autochthonous micro-algae and detritus and allochthonous invertebrates. We know what that means, right? Yeah...Music to my ears! 

Gotta find me some of these! 

Now, interestingly , I was also told be some people definitely in the know, that Fluviphylax is actually considered an egg-laying killifish... So, I guess my information might be flawed or misinterpreted...This would not be the first time, of course. We may have to take this one out of the "livebearer" category!  And of course, one hardcore scientific paper I stumbled on provided all sorts of chromosomal analytics and stuff way over my metaphorical "pay grade", but couldn't clarify this.

In fact, the discussion section included THIS line: "All species but the type Fluviphylax pygmaeus have been described in late 1990’s, and much remains unknown about the biology, taxonomy and systematics of this group of fishes."

Helpful, huh?

Regardless- this is an unusual species of cyprinodont...whatever it is!

My next candidate group has to be the genus Pamphorichthys. The genus contains six described species, all of which look like- well, how can I say it- they look like butt-ugly wild Mollies. (Of course, 75% of people outside the livebearer-geek community would immediately tell you that, "All wild Mollies are kind of ugly", so I'm staying out of that debate...). Interestingly, they are more closely linked to Mollies than any other type of livebearer, so even with my relative lack of knowledge about Mollies, maybe I'm on to something!

(P. hollandi. Image by Marcelo Fulgencio Guedes Brito)

They are true, undisputed livebearers, which is cool, and the interesting part about these fishes is their range. The genus name means "Fertile Fish", which might tell you something here! In addition to The Amazon/Orinoco/Guyana region, its members are found in The Tapajos and The Xingu! Habitats, that, although not really "blackwater", are kind of in our "softer, acidic" target range... Getting closer, huh?

One type locality mentioned for P. hasemani is "Paraguay River drainage", also kinda close to what we're thinking about, water-wise, perhaps? The typical pH of the Paraguay River is 5.8—7.4 in the upper part and 6.3—7.9 in the lower part of the river. So, like all over the place, but... And, of course, the Paraguay River ranges from being described as "sediment rich" water to clear...I mean, pics I've seen of this river look "brown", but...

However, no exact mention of "blackwater" specifically as respects to the habitat of this fish in any of the research I've found thus far...


And then we have Alfaro cultratus, which hails from Costa Rica, Panama, and Nicaragua, and is supposedly found in creeks, streams and other waters with an average pH of 6.8, and a hardness of around 5 dGH...It's a fish that is kept in the hobby, and even has a "common name"- the "Knife Livebearer'. I know a number of livebearer specialists who swear that this species does better and looks better in softer, more acidic water...particularly its reddish highlights in the scales and fins (No, seriously, it has them!). And it does have a certain "look" that would make it fit in with those flashier fishes, doesn't it?

(Alfaro cultratus. Perhaps the best candidate yet for a "blackwater livebearer?" Image by Haplochromis, used under CC BY-SA 3.0)

Could this be our baby?

It could be our best match yet!

I mean, Fish Base has this intriguing passage about this species: "Inhabits waters of low to moderate velocity, between 0 and 300 m elevation. Lives on creeks of more than 0.5 m deep, in ditches and near shorelines of large rivers. Generally swims in small groups at a depth of 20 cm. Insectivorous, the young eat mainly aquatic insects and the adults feed specifically on terrestrial insects."  One collection locale was listed as "..a rapidly flowing rainforest stream." 

Intriguing? Yes. A perfect fit? Hell, no. I mean, a "rain forest stream" could mean anything, right? Yeah.

Sigh...I'm likely really trying to fit a "square peg" in the proverbial "round hole", but it shows you the depths an obsessed guy will go to...

And then, there's this:

A while back, I received my long-awaited copy of "Fishes of the Orinoco in The Wild" by our friend, Ivan Mikolji (NOTE TO READERS: GET THIS BOOK! PERIOD. JUST GET IT- you'll thank me.), and was pleasantly surprised to see a section with some members of the Family Pociliidae!

More clues!

And, on page 278 in this must-have book, what to my amazed eyes did I see but our good friend, Poecilia cf. reticulata, AKA, the Guppy? Well, specifically, a variety known as the "Orange Line Guppy." One that I have seen before! This was huge!

And, sure enough, Ivan relates his enchanting first encounter with these little beauties, in a blackwater habitat- the Rio Morichal Lago in his Native Venezuela!

He described that they tend to stay in schools in the most shallow parts of the river, and that they, "do not venture more than 1.5 meters offshore where the water gets really dark and larger fish live."

(Rio Morichal Lago, Estado Monagas, Venezuela. Image by Cesar Perez)

That was all I needed to hear, but the accompanying photo really let this sink in: A small group of these fishes in tinted waters, with a gently sloping sandy bottom, covered in decaying leaves, twigs, and botanical materials! Ivan indicates that the pH in this habitat ranges from 4 to around 5.5- undisputedly acidic; conditions which we seldom seem to associate with livebearing fishes! 

They're beautiful little fish, with the males possessing an unusual pinkish-orange  horizontal line across the body, with a small almost black marking at the caudal peduncle. They also possess a smaller, less distinct black spot behind the pectoral fins. The females are "generic livebearer silver-grey."

I've also seen these fishes on sale from various breeders listed as "Campona Guppies" or "El Salto Guppies", collected near Ciudad Bolivar, 50km east of El Tigre in Venezuela, in the same Rio Morichal complex Ivan refers to in his book. Curiously, despite the common moniker 'Guppy", most of the hobby listings I've seen indicate that they are Poecilia wingei ‘Campona’ (you know, like "Endler's Livebearers), so there is much taxonomic confusion, to say the least!

All that being said, these are very intriguing fishes to me. Whatever the hell they're called.

 So, yeah, if you look hard enough, you'd be surprised at what you can find...


An utterly engrossing group, with amazing colors, diverse spawning habits, and adaptability, the attributes of killifishes should make them some of the most popular fishes in the hobby!

Yet, they're most definitely NOT.

PROBLEM: The general hobby doesn't have a good understanding of just how amazing these fishes are.

To me, the reasons above and many others have kept them "top of mind" for me over the years, even though I may not always have kept them consistently.Their relative difficulty to obtain has sort of added to the mystique for me. That and the fact that they typically will not have "common names", and are generally referred to by their scientific name, followed by a geographic locale and some other numbers makes them all the more alluring to me!

Hmm... "geographic locales" never scared anyone here, right?

Yet, I digress... These arcane species names don't help in the splashy, superficial "Insta world" of social media that we've created I the 21st century, I admit.

I mean, shit- there's like 0.000034% chance that a fish with a name like "Austrolebias arachan, UYRT 2015-04" is EVER gonna knock off the Cardinal Tetra or Angelfish and crack the "Hot 1,000" list of the most popular aquarium fishes, right? 

Yet, the precise Latin descriptors and type localities bely a secret to those who do the work...they give us information of incalculable value about the specific biotope/habitat from where the fish hails from. And to those of us who strive to replicate- on many levels- the wild habitats from which our fishes come from, this stuff is pure GOLD! 

(Chromaphyosemion bivittatum, pic by Mike PA Calnun)

And of course, one of the things I like best about killifishes is that many come from habitats that would be perfect for us to replicate with our skills and interest. Hobbyists who keep killies may not be as into the aesthetics of blackwater or botanical-style aquariums as we are, but nonetheless, they understand the dynamics of using natural botanical materials like peat moss, coir, and leaves to stimulate spawning and provide health benefits for their fishes!

Perhaps what also attracts me to them is the fact that they are (for the most part) small, super-colorful fishes who have managed to adapt and evolve to life in very unusual environmental niches, like puddles, small creeks, temporary pools- stuff like that. And of course, these are extremely "botanically-influenced" habitats, replete with leaves, soil/mud substrates, branches, etc. The killies are intimately linked to the characteristics of their habitats, and the seasonal changes which impact them. 

It's utterly fascinating.

(Kwango Province, Congo- Image by Thomas Minesi)

Interestingly, we have seldom, if ever seen them being kept in anything other than a dedicated breeding setup with spawning mops and bare bottoms. I think this has perpetuated the popular perception that they require the dreaded "specialty conditions" (hobby vernacular for "weird shit that's hard to do..."), and the need for 200-tank setups that will turn you into the aquarium version of the "crazy cat lady", thus smashing your interpersonal relationships to pieces. And of course, this pretty much scares the crap out of the typical armchair hobbyist.

That's where we come in. 😎

I think that attempting to replicate, to some extent, the aquatic habitats from which they come would go a long way towards making these adaptable and attractive fishes more popular in the hobby! And instead of 300-odd plastic shoeboxes filled with killies, you might have like 6 different "biotope-inspired" aquariums for killies (I say that now...). That could help ensure a bit of "domestic tranquility", right?

How you manage your interpersonal relationships is your call- but I think we can help make it a bit easier with our approach, right? 😆

(Fp. amieti, pic by Mike PA Calnun)

Sure, some killies may be shy, skittish, aggressive, come from soft, acidic water, brackish(!), or whatever- but the last time I checked, we have this...global community of skilled, adventurous aquarium hobbyists playing with blackwater, botanicals, and the availability of all sorts of "twigs and nuts" to create all kinds of specialty aquariums.

And we are into some pretty geeky stuff, ourselves, right? That makes us THE community to tackle fishes like killies in a new way.

Now, there are literally hundreds of species of killies to choose from, running the gamut from top-spawning species which deposit eggs in floating plants, to the famous South American and African annuals, which deposit their eggs in the mud and sediments at the bottom of the temporary pools which they inhabit, so it would be impossible to "generalize" a biotope-inspired "generic" setup for all these types. However, one could create a more-or-less "generalized" setup for say, species which come from small African streams and pools. 

Granted, this is different than what "hardcore" killie breeders will do- and not as efficient for breeding as setting them up in bare tanks/plastic sweater boxes with spawning mops- but it's a different way to enjoy these unique fishes, and to celebrate the unique ecological niches from which they come! I simply don't think that we as killie fans have done a great job "de-mystifying" these fishes and their needs. As mentioned above, we have seldom, if ever see them being kept in anything other than those "utilitarian-looking" dedicated breeding setups with spawning mops and bare bottoms- and lots of people assume that is THE way.

It's not. It's just a DIFFERENT way.

Another of the many things that we need to do. Another of the many directions that we can go in our hobby. It's all important. It's all fun. It's all stuff that "moves the needle" forward.

We've all got something to contribute when we tackle this "to do list" and get some cool stuff done!

Stay excited. Stay resourceful. Stay diligent. Stay inspired...

And Stay Wet.


Scott Fellman

Tannin Aquatics 



It's only a "fail" if you make it one...

Part of the aquarium hobby experience is screwing stuff up.

There are so many things that we do as aquarists which involve variables beyond our control, that failure in some things is almost inevitable.

And, after a lifetime in the hobby, I will occasionally reflect back on some of the great successes that I’ve had...and on some of the many, many failures that I’ve been involved with! Failures aren’t that bad, really. In fact, they're pretty damn helpful...As the sayings goes, “Nothing is ever wasted- it can always serve as an example of what NOT to do!”


Yeah, because if you learn from them, failures or disasters are extremely valuable tools for self-education.

I was thinking about my worst-ever aquarium disasters, and, fortunately, there have not been all that many...However, the ones I have had have been notable...and very educational!

My biggest mistakes came out of my own arrogance, really. Yes, arrogance. A desire to flaunt the "rules" set by Nature. 

Usually, they were "created" when I tried to do something that disregarded simple logic (and a century of aquarium common sense), like trying mixes of fishes that were absurd, or overstocking tanks...stuff like that.

For example, from my reef keeping experience- not all that many years ago, actually- I was going to be the ONE reefer to keep several Centropyge angelfish in his reef, including a Lemonpeel, Vrolicki, Coral Beauty, Flame Angel, and Bicolor! If you don't know anything about the dwarf angelfish of the genus Centropyge, the one thing you SHOULD know is that they are very territorial, and don't generally get along with others of their own species. And mixing different species is a traditional "recipe"  for disaster.

Oh, and most of the ones I wanted to keep had a well-earned reputation for snacking on coral tissue...What could go wrong here?

This was a recipe for failure that even the most inexperienced reefer could see coming. Of course, I was "experienced", so I knew better, right?


Nonetheless, I really thought I could pull this off in a large reef with specialized aquascaping... I was convinced that it could work and that I'd be the envy of the reef aquarium world for doing so...Not only did this experiment end with some "predictable" results (a lot of nice corals getting snacked on), it resulted in 5 very ticked-off, very beaten up dwarf angels! No shit? Who would have seen that coming, right?

Just plain stupid...For some reason, I really thought that my “methodology” would pay off and that it could work...WRONG.

But hey. I did it. I failed at it. I OWN it.

I distinctly remember a dubious experiment on the side of my parents' house one summer when I was a teen, attempting to culture mosquito larvae...yeah, you know how well THAT went down!  I think that was the most mosquito bites I've ever had in one summer...

But I learned my lesson....

Or the time I tried to build my own fluidized reactor. It sounded like noble project, but the reality was that I started with a bad concept and used cheap PVC materials that didn't quite match up. Yeah, it didn’t work, and the resulting leaks and total lack of functionality reflected my DIY "skills!" It was a good thought, but really poor on the "execution" side.

Completely unlike the Angelfish fiasco, which was a “lose-lose” proposition! Nowadays, if I have the urge to do DIY, I simply break out the credit card and purchase whatever it is I was thinking of making. Aquarium equipment manufacturers LOVE me!

Another lesson learned.

Oh, or there was that time I tried to make a continuous-feed brine shrimp hatcher...Shit, do you know how LONG it takes to get brine shrimp eggs out of the water column in your tank?

A really long time.

Enough said.

However, failing- and I mean this in the most literal sense- can actually be beneficial in so many ways, especially if you share your failures publicly. Right now, somewhere out in the aquarium hobby world, there is another hobbyist contemplating one of the same absurd, disaster-inevitable ideas that you brought to life...

Perhaps it's not some huge, epic-disaster-bound system failure...Maybe, it's just something that's a bad decision; one that should be aborted on, but isn't likely to be- and the outcome is already well known in the hobby...


Maybe it's in our nature as hobbyists; we just love to tempt fate. And look, I get it...I've written on these very pages that sometimes, we need to go against the grain and try new ideas.

Even after 6 years of pushing this idea of botanical-style aquariums, we're still learning some new ideas, creating "best practices", and evolving techniques. We still make a few mistakes. And, like many hobbyists, we're still trying to get our heads around the "big picture" of the approach, which seems so contradictory to what has been passed down as "the way to do stuff" in the hobby for generations. 

It makes many people uncomfortable to take leaps of faith. And, sure, despite the successful implementation of these techniques for several years by thousands of hobbyists, there is always a chance of failure.

It's scary. It can be viewed as "irresponsible" by some. At the very least, you might question the efficacy and safety of some of this stuff.

It makes sense.

We ask you to make a lot of mental shifts accept some ideas which seem to go "against the grain" of long-held hobby "best practices" and philosophies of aquarium management.

We ask you to understand what you are doing what you are doing, and what the rationale behind the approach is.


One thing that you do get when ideas are shared like this is the benefit of the body of work; the experience- good and bad- of a large community of hobbyists who have went down this same path. The key to taking an idea from "fringe" to "best practice" is sharing. 

Sharing of mistakes made, the refinements done, and the "tweaks" that yielded consistent success.

It starts by creating a hobby culture of sharing.

Sharing of our mistakes is every bit as important as sharing our amazing successes.

So imagine, for a moment, if you do a quick “confessional” post on Instagram or Facebook about your biggest aquarium screw up, and just one hobbyist who is contemplating a similar thing stumbles on it, and then decides NOT to recreate your disaster!

Think of the savings in money, frustration, and innocent animals’ lives...It’s all good. "Failure" makes you a more successful aquarist- IF you learn from the mistake, and IF you share it with others!

It's kind of fun, too!

So, don’t hide your failures.

Discuss them.

Trumpet them from the highest mountain. Savor them. Run around, scream, share, yell at people if you must...But tell ‘em that you screwed something up...Tell them how, why, and what it was that you did to screw it up! 

Then laugh about it and feel better! Look at the absurdity of the thing you did.

Of course, some seemingly counter-intuitive ideas do work.

Sometimes, you try something that YOU think will be a mess, but your friends know will work, because they've done it many times, and have refined the idea and practices. You're a bit scared...and you do it anyways based on their ideas!  And it DOES work! Like recently, when my friend convinced me to try several male Apistos of different species in my display tank...I was like, "Dude...really?"

And he said, "Trust me."  And I did. And it was awesome!

Think about "failure" in the context of the bigger picture...

The neat thing about mistakes, screw-ups, and "failures" is that they often lead to something far, far better than whatever it was that you initially failed at. Because, if you take the time to ask yourself why it happened, and reconstruct the process, and make necessary adjustments and recalibration, you'll often find that the idea can work- just in a slightly different manner than you originally thought. 

And failures are only failures if you don't learn from them.

Even in our business, we screw up shit all the time, and usually it's our own fault. And we try to learn from them and refine our processes to make sure that they don't happen again.

In fact, I've been working on a piece on the many screw-ups we’ve made here at Tannin. It’s actually kind of funny, because there ARE so many! 

"Marketing blasphemy", you say? No. Not at all. Rather, it’s a living embodiment of practicing what we preach...

As humans, we all make bad decisions from time to time. Some are the result of pushing boundaries...others are simply bad judgement. Again, how the mistake was made isn't quite as important as learning from it is.

We will all benefit from being human, being honest, and getting through our trials and tribulations in fish keeping together. And yeah, we all have more to gain than to lose from sharing our mistakes.

Trust me.

What’s the biggest screwup- the worst mistake- that you’ve made in aquarium keeping? What did you learn from it?

Don’t be shy. Own it. Share it. Your "failure" will likely lead to others succeeding...So, it wasn’t really a failure after all, right?


Stay bold. Stay thoughtful. Stay honest. Stay curious. Stay experimental...

And Stay Wet.


Scott Fellman

Tannin Aquatics

June 14, 2021


Sorting it out...Naturally.

Even though we might not think of it as such, the aquarium hobby is all about process...and change.

As we've gone deeper and deeper into the practice of natural, botanical-style aquariums, we gained a lot more confidence with them- the inevitable benefit of experience. And sometimes, experience breeds content or even complacency...and that's when we have to be careful.

Relying on natural processes- and fostering them in our aquariums, without understanding the "operating system"- can lead to some bad outcomes on occasion. I mean, just because you've decided to go down the road of adding leaves, seed pods, bark, etc. to your aquarium doesn't mean that it's all "peachy" and that a successful aquarium is guaranteed.

You need to have an understanding of the "why?" and the "how?" part of this. Just what is it you're trying to accomplish? 

You still have to follow all of the basic rules and tenants of aquarium husbandry. Just because we're playing with a different "system" and embracing a different look and function in our tanks doesn't mean that you can "blow off" every husbandry principle we've developed in the hobby for the past century.

If you do, it's likely that bad shit can happen.

Nature can be a rather unforgiving place.

We've discussed this idea many times in regards to our hobby. Like, how if you flaunt Nature and blow off her "rules" and proceed forward without due regard for, or understanding of, her processes, you'll get your ass handed to you. We've seen it tens of thousands of times over the years in this hobby; we'll likely see it thousands of times more in the future, too. 

And it's not all bad, really.

Sometimes, the lessons learned from these misadventures- and the surprisingly easy ways to resolve them- can yield some practical, transformative results!

Yes. They can. If we try to understand, then solve, the problem. If we don't quit.

And, quite frankly, I've been surprised over the decades by just how many so-called "problems" can be solved in aquariums by simply NOT doing some radical moves. In fact, I've been surprised by how many things that we label as "problems" aren't really problems! For example, by enduring the "ugly" early phases of a tank, or by waiting out the initial bloom of fungal growth and biofilms and understanding/appreciating them, or by persevering in an algal bloom (after educating oneself as to what caused it to happen in the first place), etc.  

Adjusting our tolerances to how much we can handle. And understanding that some of the stuff we see as unsightly isn't. Rather, that it's exactly what you see in Nature; it's what you should expect. 

You generally need to just...hold. Ride it out. Wait. Be patient.

Now sure, some stuff that happens in our aquairums needs immediate action: Disease outbreaks, heater malfunctions, aggressive fishes, etc. Other things require something not every hobbyists has in his or her "toolkit"- the ability to look beyond the immediate and to understand what could have caused the situation, and to understand that the simple passage of time is a great "fix" for many things.


And a little faith.

Faith enough to just ride it out.

Yeah, I know that's hard for a lot of us.

However, often excessive intervention in biological processes in an attempt to "fix" them, ends up circumventing some other, vital aspect of the process, to the detriment of the entire aquarium ecosystem. As we've said many times, removing decomposing botanicals, for example, deprives some of the beneficial organisms in our systems their food source, which has broader implications for the ecology of your tank and its occupants.

Yes, many times, we simply need to wait through things which seem "wrong" to us because of our experience in the hobby; however, they are often totally normal in Nature- yet just outside of what we have come to expect in the hobby.

A case in point is some of the substrate experiments with my "Urban Igapo" idea that  I've shared with you over the past several years. This is stuff that I had been working on for years, and it reached the point where I just taught myself to expect certain things to happen, and to understand that they will pass or change over time if I leave things alone.

It was about looking at things differently and not letting our biases or the 'burden" of past experiences taint our outlook...

For example, the substrate formulations I've developed  for "Nature Base Igapo" and "Nature Base Varzea", are designed to be part of a "process"- perhaps even a "technique", of taking a tank through various phases: A dry "terrestrial phase", then a gradual inundation period, then a fully aquatic phase, and then a drying phase again. It's a different way of doing a tank- and a different set of characteristics and expectations accompany it.

Can you use it simply as a substrate in a "wet" tank?

Of course. You just need to understand how it works; what to expect: A bit of turbidity for a few days. A different initial "outcome." 

One that yields some different results, and takes a slightly different path to the goal we have in mind. Not "bad"- just "different."

That's all.

By understanding the story behind the product, and what it was intended to do, which we've talked about a lot here over the past year or two, you can have a complete understanding of how to use it, what to expect from it, etc.

The good, the bad, and the ugly.

And this sedimented substrate is proving very popular in our community, with all sorts of cool experiments taking place...because you understand what to expect from the stuff. You know that Nature will "sort it out" over time.

It's simple, in the case of "NatureBase.

The most important thing you'll need when you use the stuff is understanding... A mental "buy-in" to a process which goes against most of what we expect from aquarium products. That doesn't come with a bag of dirt, no matter how col the packaging is- trust me.

When you initially wet a substrate consisting of soil, clays, and sediments, you realize that you're going to get horrifically turbid, cloudy water.

It can last for a few days, or perhaps a week or more.

And again- that's okay..

Because you need to go into working with this material understanding that it's not intended to look or function like a normal aquarium sand. That's not what it's about. You don't rinse the stuff. What do you think will happen when it gets wet?

It involves process. Patience. And the passage of time.

Hell, you're not even going to use the stuff to create a "typical" aquarium in the first place! It's so important to understand the "how and why's" of specialized aquariums when we embark on these journeys. 

Yeah, this is sounding like an "information-mercial" for our product, but it's more about the broader theme of process and patience.

It's a tangible example of a "process" that requires not only a different outlook and set of expectations, but a mental "buy-in" to a system of doing things for a reason. Sure, you can fill a tank with NatureBase with water 100% full from day one, and have a "supercloud" of sediments and mud for a few days or a week. It's okay. 

Nature will simply adjust the initial outcome.

Leave it alone and let Nature "sort it out" herself!

Either way, Nature eventually sorts it out.

Again, this mindset of "zen-like patience" and confidence in Nature "figuring shit out" is but one way of looking at and managing things- and it's not for everyone. 

Control freaks and obsessive "tinkerers" need not apply.


Intervention, in this case, is more mental than actual. We need to change our thinking! Not every process has- or needs- a "workaround."

The "workaround" is to understand what you're doing, what could happen, WHY it happens, and what the upside/downside of rapidly "correcting it" can be. The key, typically, as with most things in the aquarium world, is to simply be patient. 

Despite our best efforts to "fix" stuff- Nature almost always "sorts it out"- and does it way better than we can.

Think about the bane of most hobbyists' existence- So-called "nuisance algae."

It's a "nuisance" to us because it looks like shit.

To us.

It derails our dreams of a pristine aquarium filled with spotless plants, rocks, coral, etc. Despite all of the knowledge we have about age being fundamental for life on earth, it bothers the shit out of us because we think that it looks "bad."

And collectively as hobbyists, we freak the fuck out about it when it appears.

We panic; do stupid things to get rid of it as quickly as possible. We address its appearance in our tanks. Seldom do we make the effort to understand why it appeared in the first place and to address the circumstances which caused it to proliferate so rapidly. And of course, in our haste to rid our tanks of it, we often fail to take into account how it actually grows.

Algae will ultimately exhaust the available excess nutrients which caused it to appear in the first place, if you take steps to eliminate "re-supplying" them, and if you wait for it to literally "run its course" after these issues have been addressed.

We've seen this in the reef aquarium world for a generation now. It almost always passes- once we address the root cause and allow it to play out on Nature's time frame.

Of course, as fish geeks, we want stuff to happen fast, so hundreds of products, ranging from additives to filter media, and exotic techniques, such as dosing chemicals, etc. have been developed to destroy algae. We throw lots of money and product at this "problem", when the real key would have been to address what causes it in the first place, and to work with that.

Yeah, the irony is that algae is the basis of all life.

In a reef tank (or freshwater tank) it's a necessary component of the ecosystem. And hobbyists will often choose the quick fix, to eradicate it instead of looking at the typical root causes- low quality source water (which would require investing in an RO/DI unit or carbon block to solve), excess nutrients caused by overfeeding/overcrowding, or poor husbandry (all of which need to be addressed to be successful in the hobby, always...), or simply the influx of a large quantity of life forms (like fresh "live rock", substrate, botanicals, corals, fishes, etc...) into a brand new tank with insufficient biological nutrient export mechanisms evolve to handle it.

And often, a "quick kill" upsets the biological balance of the tank, throwing it into a further round of chaos which takes...longer to sort itself out!

And it will sort itself out. It could take a very long time. It could result in a very unnattractive tank for a while. It could kill some fishes or plants. I mean, Nature "mounts a comeback" at nuclear test sites! You don't think that She could bring back your tank from an overdose of algicide?

She can. And She will. 

In due time.

Once these things are understood, and the root causes addressed, the best and most successful way to resolve the algae issue long-term is often to simply be patient and wait it out.

Wait for Nature to adjust on her terms. On her time frame.

She seeks a balance.

So, it's really about making the effort to understand stuff.

To "buy in" to a process.

Nature's process.

To have reasonable expectations of how things work, based on the way Nature handles stuff- not on our desire to have a quick "#instafamous" aquascape filled with natural-looking, broken-in botanicals two weeks after the tank is first set up, or whatever. It's about realizing that the key ingredients in a successful hobby experience are usually NOT lots of money and gear- they're education, understanding, and technique, coupled with a healthy dose of patience and observation.

Doing things differently requires a different mental approach.

We work with Nature by attempting to understand her.

By accommodating HER needs, not forcing Her to conform to OURS. Which she won't do in a manner that we'd want, anyways.

Nature will typically "sort stuff out" if we make the effort to understand the processes behind her "work", and if we allow her to do it on HER time frame, not ours. Again, intervention is sometimes required on our part to address urgent matters, like disease, poisoning, etc. in closed systems.

However, for many aquarium issues, simply educating ourselves well in advance, having proper expectations about what will happen, and (above all) being patient while Nature "works the issues" is the real "cure.

So yeah, in our world, it's never a bad idea to let Nature "sort it out."

She's done a pretty good job for billions of years. No sense in bailing out on her now, right?

People ask me why I cringe and react so negatively when I see commercial brands, hobby groups, etc. make prosaic statements like, "We're inspired by Nature" or "We seek to replicate Nature", etc. in their marketing. It's not because I think I'm all bad ass and they're all stupid. Of course not. It's because touting the "look" of Nature without accepting and understanding the processes and aesthetics that she utilizes in order to achieve them is really only half the story.

"Sanitzing" and 'editing" Nature to ignore or bypass the parts that we find "offensive" somehow is missing the whole point.

I'm not saying that we all need to achieve PhD's in biology to "appreciate" Nature. I'm not saying that a truly successful aquairum can only be achieved when the tank looks like shit.

I'm merely saying that we need to really make the effort to understand natural processes more. What causes them. What they mean. Why they create the looks that they do. A simple idea. Yet, it's something that will yield enormous benefits to us as aquarium hobbyists.

We simply need to push ourselves a bit harder to understand, rather than just buying into some marketing hyperbole or regurgitating Amano's words and philosophies without actually considering them and making the effort to understand just what the hell he meant by them.  

We need to look at Nature as it really is.

We need to make the effort to understand Her processes.

We need to accept the way She looks and functions.

Without accepting all of the stuff that we as aquarists think is "ugly"- you know, biofilms, tinted water, decomposition, algal patinas, etc., we simply deny ourselves the opportunity to truly understand and appreciate her wonder. To learn how she really works- and how to truly work with her.

Yes, these are things that require a mental shift- a "buy-in" to her process.

Work WITH her, not against her. We've said it thousands of times here over the years, and we'll no doubt say it again and again.

Because it's so damn fundamental to what we do. But into this mind set. Learn. Understand. Let Nature sort it our without "intervention" sometimes. 

Trust me- it'll change your hobby experience for the better. Forever.

Stay studious. Stay observant. Stay patient. Stay diligent. Stay open-minded...

And Stay Wet.


Scott Fellman

Tannin Aquatics 

June 10, 2021


To "Bee" or Not to "Bee?" The Surprising Bumblebee Goby

One of the fun things about the aquarium hobby is that we always have the opportunity to find out new things about existing ideas, practices, and fishes. There are certain fishes which we have almost taken for granted in the hobby, yet, which there still seems to be a lot of conflicting information about circulating online and elsewhere.

I sometimes wonder if this is because there is that whole "regurgitation" thing going on- a lot of well-intentioned "information aggregating" about an aquarium topic from individuals with little to no personal experience with an idea, technique, piece of equipment, plant, coral, or fish.

Perhaps this has lead to us becoming weirdly complacent in our understanding of such things? As hard as it is to believe, there are some very common (to the hobby) fishes which fall into this grey area.

My vote for the cutest freshwater fish is definitely the lovable "Bumblebee Goby", Brachygobius doriae. because, well- it's really small ( like maybe 1.5"/ 38mm max), and hops around like its namesake.  And it has this little face that's...well, it's cute. And, did I mention? It's small. It's even placed in a small genus, with only nine, occasionally-confused members.

Actually, not occasionally confused- pretty much always confused! 

And, the real irony is that the fish which we in the hobby refer to as the "Bumblebee Goby" is Brachygobius doriae; however, "the books" always seem to illustrate and talk about the similar, but exceedingly rare Brachygobius (Hypogymnogobius) xanthozonus. It's super easy to be totally confused about these fish. The collective "Bumblebee Goby" moniker that we as a hobby and industry attach to all of these little bastards doesn't help at all, either!

Don't feel bad. It's not just us hobbyists who are making a confused mess of this stuff. Goby taxonomy is apparently, "...a Category 5 Shit-storm!" as one taxonomy student I reached out to for this piece relayed to me! Love the honesty of college kids! 

Now, one of the things I love about this fish is that it's one that we have  a completely preconceived notion about, and the "Bumblebee Goby",  is like the poster child for "little brackish aquariums."

(The star of our blog...taken by our good friend, Ted Judy! Visit his site- tedsfishroom.com for all sorts of cool stuff!)

And, yeah, it IS found in brackish environments in places like coastal southeast Asia, from the Mae Khlong in Thailand to the Mekong basin (Cambodia, Laos, and Viet Nam), Malaysia (Peninsular and Sarawak areas), Singapore, Indonesia (Kalimantan, Borneo) and Brunei. 

There is one species, Brachygobius xanthomelas, which is, from every source I can access, a true freshwater "specialist"- not believed to inhabit brackish water habitats.

And then there is the confusing and similar B. sabanus, which really looks like B. doriae, and is found in both brackish and freshwater habitats, and...Yeah. I actually think I've kept that species before, having been simply and exasperatingly called "Bumblebee Goby" at the retailer.

According to one source, the two species are extremely similar in appearance and easily confused, with the primary visual difference (to us, not ichthyologists doing scale counts) is that in B. doriae, the majority of the first dorsal fin, and about 2/3 of of the pectoral fin are black. In B. sabanus, the last ray or two of the first dorsal fin are clear, and a small percentage of the pectoral fin is black. 

Yeah, try to determine THAT on a 1-inch fish in an established aquarium! I kind of understand why we use the common name to describe all of these little fishes now!

Oh, and supposedly B. sabanus is much smaller than B. doriae... Okay, but seriously....They're both tiny-ass fish! 


I'm pretty sure that the fish in my brackish tank is B.sabanus, but I"m not 100% certain...Not that I'm easily confused or anything like that...😆


The real cool thing about our little friends, Brachygobius doriae and Brachygobius sabanus (or whatever the hell they are)is that they may be found in not only "regular" freshwater habitats- but soft, acidic freshwater...like those tannin-stained peat swamps that we've talked about before!

Now, in these peat swamps, they surprisingly tend to be found in waters that are more mildly acidic (like 6.8 and up), but nonetheless, this is an extraordinary range for a fish that has been long ago "typecast" by the aquarium trade as a primarily brackish water fish, wouldn't you say?

Now, most aquarium-available populations of these fish tend to come from pure freshwater, or if we're lucky, brackish. The problem is that we as hobbyists are at the mercy of our suppliers to advise us where they came from. Once you identify what species you actually have, if that's your thing- careful acclimation to your water conditions- whatever those might be- is necessary. Like a lot of small gobies, they tend to not tolerate wildly fluctuating environmental conditions well.

I've kept them in brackish (SG 1.003-1.010) water with a little "tint" and perhaps a slight turbidity to it for many years with great success (and I even had two instances of them laying eggs!). Our concept of the "botanical-style brackish" aquarium is pretty much a perfect fit for these little guys, IMHO...assuming you carefully acclimate them to your conditions. 

And being a little fish that tends to hop around on the substrate, it's not a bad idea to learn more about the substrate in the localities where it's found, right? I did a little digging (LOL) in the available scientific information on these fishes and their common habitats, and found that the locations in which they are found tend to have fairly specific types of materials in the substrate. 

The substrate itself is typically muddy, sandy, silty and interspersed with leaves, driftwood, and yeah, mangrove roots in the brackish areas. Did you see the "leaves" part? Yeah...kinda what I was thinking. I love the mud part- a theme that we've been talking about aover and over here at Tannin, haven't we?

I've always kept these little guys in "community" settings- that is- a community of their own species. Like, a group of 10-20 specimens.  I suppose the this "big community" approach is a bit "unconventional" in aquarium hobby practice, but if you want to see their most natural behaviors, this is the best way, IMHO. They remind me very much of marine Jawfishes, in which there are definite social hierarchies and territorial boundaries and such.  

You don't need a huge aquarium to keep them, but wouldn't it be cool to keep a bunch of these tiny guys in say, a 40-50 gallon tank? Yeah...Of course it is! Especially if it's set up correctly!  That's a proportionately huge tank for some tiny little fishes, but trust me- it's the ultimate "stage" for these guys!


Of course, careful acclimation and quarantine of newly-received Bumblebee Gobies is really important, because they're little fishes, and are often half-starved upon arrival at the LFS. They do need ample time and attention in order to acclimate to captivity healthily.

And the way you set up the tank; the way it's "scaped", is so important to facilitating their health, happiness, and interesting behaviors! This is where not just relying on aquarium references is important. Look on sites like fishbase.org, and see the "occurrences" of the fish, and research these collection sites...You'll find out a lot about these locales if you "deep dive", and you can find out lots of interesting details about the ecologies of the areas in which they are found in Nature.

The importance of setting up an aquarium with a variety of "micro-niches" (i.e.; rocky areas, empty shells, branches, palm fronds, leaf and botanical accumulations, mangrove roots, etc.) cannot be overstated. Not only does it look cool aesthetically (duh..), it facilitates social behaviors, provides potential food sources, and as well.

Having decomposing leaf litter and sedimented substrates provides the opportunity for these little guys to forage among- important, because it is sometimes a bit of a challenge to get them to feed on prepared foods. I've found, however, that they will typically acclimate to frozen and live brine shrimp, and even Daphnia, over time. The botanical-style aquarium gives you that additional "edge", providing supplemental food sources, as we've discussed many, many times here.

As I have mentioned already, it's great to keep these guys in a group- the larger the better, IMHO! This is why a decent-sized aquarium makes the most sense to me! 

Now, one of the things we've learned over the decades is that just because you're small doesn't mean you can't be a bit of a jerk- and these guys are no exception! You'll occasionally get a dominant male that is just such a...well-asshole- that he pretty much can be the "top dog" of his domain of tiny friends, making life sometimes miserable for them.

You need to watch this type of behavior and occasionally intervene to make sure it doesn't get out of hand (and it can, believe it or not...seeing two 3/4" fishes going at it is only partially funny when one of them gets the shit kicked out of him).  Again, that's the value, IMHO, of using a much larger aquarium than you'd think that you need for these guys.

(Image by Dirk Golinski, used under CC-BY-SA-3.0)

Perhaps my favorite aspect of these fishes is that many of them ARE truly brackish-water fishes, or at least, brackish-water "friendly", and are truly worthy of their own tank. A group of these small, endearing fishes can be as exciting as any of the larger, flashier fishes which we associated with brackish tanks.

And since we have a better way to do brackish, IMHO, we can leverage this ability with better understanding of the habitats from which these guys come from in Nature, and create truly amazing displays for them!

The frequent frustration many hobbyists encounter when they embark on a brackish water aquarium adventure is a distinct lack of readily-available information on the fishes and and their habitats.  And of course, there is a significant challenge to source some of the fishes from these unique habitats...and, indeed, it's often a matter of discerning which fishes indeed come from brackish water habitats!

As we start looking closer and closer at brackish aquariums, we'll start looking more and more closely at the fishes that we could use in our brackish aquariums. This piece was not intended to be a landmark, group-breaking expose' on a pretty well-known fish...

However, I wanted to get you thinking about some of the fishes that you've already heard of, perhaps even taken for granted, while looking at them in the context of the type of environments we're talking about with our botanical-style brackish work.  

Of course, we look at some of the common (and rare) fishes that are perfect for what we're doing. The "Bumblebee Goby" (whatever species you might encounter), is one of our enduring, yet surprising faves, for a lot of reasons. 

Should you keep this fish? Well, sure, if you're up to the idea of really setting up the correct conditions for the species that you have. They're simply not a super-easy fish that you can just pop into any old tank...They're not difficult, either, but you need to understand your fish and the habitat which they came from in order to really be successful with them, IMHO.

We're thinking of lots of cool ideas to keep these fishes healthy and happy for a long time...and no doubt, you have many of your own! Be sure to share, because we love to hear what you do, too!

Stay excited. Stay creative. Stay "slightly salty..."

And Stay Wet


Scott Fellman

Tannin Aquatics 




June 08, 2021


"That peat moss thing"...again...


After a bunch of years playing with botanicals, we've learned a lot of stuff. We've screwed up a lot of stuff, too! Yet, almost every day, we learn some new things that are really exciting and cool

And we get questions. Lots of questions.

A question we get a lot around here is about the "water-softening capability of botanicals", to which I respond almost reflexively, "There is none." Botanicals will not help you soften hard water.

I believe that anyone who tells you this categorically simply does not have the correct facts. Ask them to explain how this process occurs. I'd like to know, 'cause I've found no evidence of this! 

Hobbyists really want an inexpensive, "natural", or simple way too soften their water. Using some botanical-based stuff just seems so right, doesn't?

Well, we also get a ton of questions about peat moss...mainly, what it can do in aquariums, and why we don't carry it. 

We'll get to that part in a minute.

Let's talk about peat moss in general for a bit. There is a lot discussed about peat's ability to "condition" aquarium water. And, although some of the facts might a bit convoluted, there is some validity to this.

Yes, interestingly, it is known that our old and controversial friend, peat moss, has actually demonstrated some capacity to conduct ion exchange ( a process in which which unwanted dissolved ions in water are exchanged for other ions with a similar charge.) Ions are atoms or molecules containing a total number of electrons that are not equal to the total number of protons. (I know, if you're like me, that made your head start spinning almost instantaneously.😳

Think of it this way: Peat softens water by exchanging humic acids for magnesium and calcium.

It's actually true.

Peat effectively binds calcium and magnesium ions, while simultaneously releasing tannic and other acids into the water. These acids "work" the bicarbonates in the water, reducing the carbonate hardness and pH to some extent.

And it will tint the water, as we all know.

Interesting, right?

However, you can't just drop some peat into your tank and expect "Instant Amazon." This process requires "active peat filtration" (the water passing over over the peat itself) to make this happen. There's more to this, and we'll touch on that in a minute.


So, what doesn't Tannin offer this stuff?

Well, there is that ethical question about peat being an ecologically non-sustainable product. Now, for decades, aquarium hobbyists used peat moss for the purpose of lowering aquarium pH, creating "tinted" water, enriching planted substrates, and for spawning killies and other fishes. It's easy to use, comes in a few forms, and definitely "works as advertised" when it comes to aquarium use! 

Now, in all fairness to us, the bulk of the peat moss harvested worldwide is used in the horticulture field, and aquarium use likely accounts for the tiniest percentage of worldwide peat consumption. Nonetheless, its use for aquariums has been discouraged in recent years as we take on a more environmentally conscious, sustainability mindset. That's cool!

And I suppose, if it follows the sort of way the aquarium hobby is treated by the media and environmental groups when it comes to related issues, such as fish collection and such (just read up on the Hawaii fish collection ban for more on that stuff) . In general, we're the easiest target- the "low-hanging fruit", without any real significant  "lobby" or industry advocacy for this kind of stuff, so it's natural that we'd be a target.

And of course, we need to self-regulate a bit. And we largely do.

Okay, so, what exactly IS peat moss...and why the controversy about its use?

"Peat moss" is the collective name given to mosses from the genus Sphagnum, which contains almost 400 species!  Peat comes from bogs, which are one of the four main types of wetlands recognized by ecologists. It's generally decomposed moss that accumulates in these bogs, which is then commercially harvested. This material been used extensively in agriculture, because it excels at retaining water: Peat plants may hold 16–26 times as much water as their dry weight, depending on the species!

Over the years, there has been a lot written about the sustainability, or lack thereof- of harvesting peat moss. It's sort of a "poster child" for the management of precious natural resources, and there are environmental consequences to removing this material from the bogs where it accumulates.

(Image by Boreal. Used under CC-BY SA 3.0)

It's been estimated by scientists that peatlands store a third of the world's soil carbon, and their harvesting and use releases carbon dioxide, the major greenhouse gas driving climate change.


Although degraded peat deposits have often been restored by blocking water drainage sources, throwing in Sphagnum seeds, and covering them with a water-retaining mulch, it's not that simple a story. Yes, restoring peatlands does help soils by improving water-holding capability; however, the bacterial respiration caused by the decomposition of the mulch and other organics in the restored deposits continues to release C02.

According to some studies, it can take several years for the photosynthetic rate of the new peat deposit to beat the "respiratory rate", meaning that there is a net loss of carbon into the atmosphere during this period of time, which unfortunately contributes to the production of greenhouse gasses. 

(Photo by Ed Blodnick)

Now, there are two sides to every story, and there are a lot of great efforts being made to harvest peat in what most would agree to be a sustainable manner. Canada supplies up to 80% of the peat moss consumed in North America, and the peat industry there has put in significant effort to create what they feel is a sustainable resource.

According to industry studies, Canada contains 294 million acres- or approximately 25% of the entire world’s peatlands! The Canadian horticultural peat industry operates on less than 55,000 acres of these peat bogs nationwide. According to the industry, the amount of peat moss harvested from Canadian peat bogs every year is nearly 60 times less than the total annual accumulation of new peat moss.

That sure sounds like they're doing something right, doesn't it?

I think so! 

Being good stewards of a precious resource like tropical fishes, we can appreciate efforts made to conduct business in a manner that respects the environment.

So where does that leave us? 

Well, to be quite honest, I go back and forth. I told myself for a long time that if Tannin offered peat products, they'd definitely be from Canadian sources, because the industry there makes a significant overall effort to manage the peatlands.

Okay, we've kind of covered the ethics here, and we have sort of validated the hobby's "worst-kept-secret" that peat can soften water.

However, is it efficient?

Um, not in my humble opinion.

Being the curious, and occasionally reckless fish geek that I am, I played around with this idea once, to try to see if this does, indeed work.

And, well, it does sort of work.

It took a shitload of peat and a fair amount of time to reduce my Los Angeles tap water, with hardness exceeding ~240ppm and ph of 8.4 down to "workable parameters" of 6.4ph and a hardness level of around 40ppm. How much are we talking? It took a full  2-cubic-foot bag of peat, added to  a 30-gallon plastic trash can, filled with with my tap water, over 8 days in order to achieve these parameters.

So, yeah. The idea does work. However....

By comparison, my SpectraPure 4 stage RO/DI unit cranks out 80+ gallons of zero TDS, zero carbonate hardness water in a day. Now, one could argue that the rejection rate of RO/DI makes it less efficient- but hell, I water my garden with the reject water! And yeah, a unit like mine retails for around $300 plus USD, more than a 2-cubic foot bag of peat, but the long-term, consistent efficiency, ecological "friendliness", and reliability is pretty obvious to me. 

All in all, for maximum efficiency, consistency, and control, just invest in an RO/DI unit and you'll create soft water with little effort and no mess.

Yeah, it IS a bit pricy to purchase an RO/DI unit, but well worth it, IMHO.

But yes, you CAN soften water with peat to some extent if you're put to it, have the means to do it, and test. I've long ago lost that thrill that some people get from these types of "money-saving DIY" methods. To me, I simply decided to forgo other indulgences, save my money for a while, and invest in  the RO/DI unit and call it a day.

You should, too.

Are there alternatives to peat moss?

Well, sure.

However, they don't offer some of the "capabilities" (ie; the ion-exchange thing") as peat, but they do tint the water, impart some tannins and humic substances into water, and offer similar soil/substrate-enhancing properties. For example, our "Fundo Tropical" and "Substrato Fino"  are coconut-based, and are derived from the processing of coconuts for other uses.

Since most coconut harvesting is done by hand, large-scale use of fula-guzzling, exhaust-emitting tractors and such is limited. And growing coconuts doesn't require pesticides or herbicides. And our coconut-based products come from smaller, family-owned operations, not large commercial farms which often raze coastal mangrove thickets in order to grow more coconuts, and have little regard for that precious ecosystem. 

It's not perfect, but the environmental impact of both of these products is substantially and demonstrably better, in my opinion, than peat. ("Yeah, but if they're shipped via airplane or deisel-fueled boat or truck..?" Okay, right...but we're talking about the production side here, so...😂 )

And of course, this discussion on sustainability dovetails nicely with the general discussion on botanicals in general. Like, how sustainable is the selection of stuff we offer?

It's not perfect. We're trying, though.

I spent quite a few years developing direct contacts with the producers of the botanical materials that we offer. Most of these suppliers are family-owned businesses in areas like Southeast Asia or India. These businesses generally grow the materials for other purposes, like fruit production, furniture manufacturing, etc. Much of the material is a sort of "by-product" from other uses.

Many of these operations are not just gathering materials from wild habitats; rather, they are harvested by hand from their own farms and land. And what's really cool is that, once you're "in" with these people, they'll often refer you to their friends or extended family who do similar work. These referrals have led to us developing some of our most trusted suppliers for cool stuff. And it's good for them, too, providing income and employment for the local communities.

The ones which collect stuff from the wild are generally doing this with proper supervision/permits on government-managed forest lands, or under the auspices of local agricultural/ ecological authorities and programs. I've dropped a few suppliers and products because I was pretty certain that they were not procured in a sound manner.

I'll continue to do this.

Yes, it will result in the disappearance of some products from our lineup temporarily, or even permanently, but it's important for us to do our part when we can.

Of course, it's not a perfect system.

Even though our supplies are often more limited than we'd like, more expensive than stuff offered by upstart competitors, and can be subject to disruption for a variety of reasons, we've always felt it best to do business this way, as opposed to hitting up large importers of stuff intended for other uses (construction, home decor, etc.), like many of our erstwhile competitors do. In addition to being of questionably sustainable origin, some of this stuff is treated with varnishes and preservatives (because it's intended for other uses), which would have deadly consequences for fishes in aquariums.( I know, because we test and use everything that we sell, and we've been burned in the past!)

Yeah, it's tedious and pricy at times. We pay more for our stuff, which, unfortunately, is reflected in our retail pricing. Yet, I think over the past 6 years we've done things pretty well. Not absolutely flawlessly, but pretty damn well!

I'm okay doing business this way. Again, it's far from perfect, shockingly inefficient  at times, and there are still some efforts I'd like to see being made by some of our suppliers to be even more ecologically friendly.

However, supporting these small, often family-owned operations has been a much more gratifying approach for many reasons. They tend to be more responsive to our customers' needs, resourceful at what they do, and it's nice to know that our dollars (and yours) go into the hands of these businesses directly, supporting their livelihoods and that of their employees. And, being on a first-name basis with the owners is very cool! It's really been fun actually FaceTiming some of these people while they're processing/harvesting/gathering the very materials they're getting together for us! 

We'll keep refining this process, even if it means eliminating a substantial portion of our offerings over time as we source more sustainable/ethical substitutes. We'll keep looking for viable alternatives and innovative offerings whenever we can. 

So, back to the "peat thing." 

I don't think that we're likely to be offering peat any time soon. Again, there are some sustainable operations out there. However, we just feel that this is a product which most hobbyists can procure themselves, or use the many cool alternatives available. There are just too many ethical considerations that we believe are best addressed by the individual.

It's neat stuff. Amazing stuff, actually. It works "as advertised", but the "baggage" that it carries with it seems a bit too "heavy" for us to want to contend with.

Besides, there are so many other interesting things for us to play with in our botanical world; we'd best spend our time looking for and creating some new and exciting things.

It's what we do.

It's what will keep moving the hobby forward.

And it's what you expect from us!

Glad to have you along for the ride.

Stay thoughtful. Stay creative. Stay curious. Stay bold. Stay innovative...

And Stay Wet.


Scott Fellman

Tannin Aquatics 





June 05, 2021


From Nature's Idea Book: Floating leaf litter beds...

If you're a geek like me, you're always on the lookout for unusual ecological niches to recreate in your aquariums. And Nature doesn't disappoint! She's got a whole array of crazy-cool habitats which we as aquarists can appreciate and attempt to replicate in our tanks.

In places like the rain forest streams of Amazonia, biologists have observed floating leaf litter beds which hold together for quite a long time- almost becoming known "features" in the aquatic "topography" of the igarapes and streams of the region!

So imagine, if you will, a "classic" submerged leaf litter bed in Amazonia, composed of a variety of leaves, branches, twigs, seed pods, and other botanical materials...Yet, floating on the water surface; extending as much as a few feet under the water! What you get is a fairly deep layer of plant materials colonized by fishes and other creatures, which forage on the macro invertebrate life found in these complex assemblages.

Biologists call this an "ephemeral" habitat, as it is transitory or temporary as it slowly breaks apart-despite the fact that it might be years before this occurs.

Okay, so it slowly breaks apart over time.

This is cool.

And often, these floating or partially submerged leaf litter banks either accumulate among the branches of overhanging vegetation during the high-water season, gradually floating downstream, or they stay anchored in place by fallen tree trunks and other large materials, ultimately forming a more "traditional" submerged leaf litter bed as they sink.

Think about the possibilities to replicate these floating leaf litter beds in aquariums!

I found this to be an amazingly interesting niche! Reminds me of the Sargassum "forests" of the Caribbean and Tropical West Atlantic! Literal "floating feasts" for the animals which reside there! This is another potentially irresistible ecological niche for us to play with, right?

Oh- and many fish species associate with these floating litter banks for the entire wet season! 

And one of the reasons they stay put is because their food sources are there, too! In fact, a species of "water bug", Weberiella rhomboides, is found almost exclusively in these floating banks, attracting large numbers of insectivorous fishes, like characins, catfishes, knife fishes, and others. 

Yeah, it's a virtual "who's who" of blackwater, leaf-litter-zone dwellers, some of which are very familiar to us as hobbyists- for example, characins like Hemmigramus species, Moenkhausia species, the killifish Rivulus ornatus, and of course, cichlids, including a number of ApistogrammaCrenicichla, Hypselecara, and the much-loved Mesonauta festivus, to name a few. Can you imagine how this could make a very interesting theme for an aquarium?

Yeah, I can...as you'd imagine!

You'd want a fairly shallow, wide aquarium, and probably would filter it with an outside power filter or canister filter with the return positioned in such a way as to minimally disturb the surface. With minimal preparation (ie; cleaning them with a light boil, but not trying to saturate them to the point of the materials sinking right to the bottom), a lot of this stuff would sort of float for a while before sinking to the bottom.

You'd essentially be creating a diverse assemblage of botanicals, just like you would if you were doing a "conventional" leaf-litter display (I love that- I just called this stuff a "conventional leaf litter display"- look how far we've come...). And of course, Nature offers no shortage of inspiring leaf-litter habitats to examine!

Now, eventually, some of this stuff would sink, or be trapped below the floating "matrix", and you'd end up with materials on the bottom...okay...cool!  It would transition naturally to a more "conventional" botanicals-on-the-bottom display. So this is essentially an "ephemeral display"- transitioning from a "floating leaf litter bed" to a submerged leaf-litter aquarium!

How freakin' cool is that?

Of course, you could probably keep it going by replacing the leaves and such as you would anyways, right? And as the wood becomes submerged, you'd "let it do it's thing", and/or replace/add new pieces.

A sort of actively-managed botanical-style tank...sort of like any other botanical-style tank- but with a twist...er, a float.

Stay creative. Stay inspired. Stay thoughtful. Stay observant. Stay diligent...

And Stay Wet.


Scott Fellman

Tannin Aquatics 

June 04, 2021


The "endless dance..."


Is there such thing as a "finished" aquarium? 

I think not. 

Yet, the aquarium hobby- a good percentage of it- is obsessed with the concept of "finished."

Part of the pleasure is working with Nature; being challenged by Her.. adjusting, pivoting, waiting. And that's what makes stuff fun!  There is no "finished." I mean, when there is nothing more to do but change water, tweak a few gadgets, and feed, is that "finished?" I don't think so.

Have you EVER gotten a tank to that stage? Where you're simply observing it and nothing else? What's that like?

Because I've never been there.

It doesn't exist, IMHO.

An aquatic display is not a static entity, and will continue to encompass life, death, and everything in between for as long as it's in existence. 

Does it ever reach "finished?" Does Nature? Of course not! Rather, it's continuous evolution, in which there might be some competition between fishes, plants, or corals that results in one or more species dominating all of the rest. Maybe. Or, perhaps diversity continues to win, with lots of different life forms eaking out an existence in your artificial microcosm, just as they have managed to do for eons in Nature?

We don't have all of the answers.

And that's okay. However, we should enjoy those times when our tanks are doing their thing...evolving...

Which is... every single day.

Yet, there is an apparent disconnect in the general aquarium hobby. A desire to get to "finished"- whatever that actually IS- as quickly and easily as possible. Like, why are we in such a goddam rush? What's the point of trying to quickly get through all of the amazing stages of aquarium development, en route to some strange and seemingly enigmatic destination called "finished?"


I was wondering if it had to do with some inherent impatience that we have as aquarists- or perhaps as humans in general-a desire to see the "finished product" as soon as possible; something like that. And there is nothing at all wrong with that, I suppose. I just kind of wonder what the big rush is? I guess, when we view an aquarium in the same context as a home improvement project, meal preparation, or algebra test, I can see how "finished" would take on a greater significance!

But an aquarium..? I mean, that's supposed to be a fun thing!

And the journey- the evolution of the aquarium- is a big portion of the fun.

Yet, I see tons of queries on forums and on Facebook groups, etc., asking about such-and-such-a technique to accelerate or circumvent the "cycling" phase of a new aquarium. Some people will spend all sorts of money and try just about anything in order to get to some more advanced phase of their aquariums' existence as soon as possible! 

In the botanical-style aquarium world, we talk so much about the need to be patient, and to just enjoy your tank wherever it may be on its"evolutionary path." This is sort of fundamental to what we do. If you look at an aquarium as you would a garden- an organic, living, evolving, growing entity- then the need to see the thing "finished" or somehow "farther along", becomes much less important.

Suddenly, much like a "road trip", the destination becomes less important than the journey. It's about the experiences gleaned along the way. Enjoyment of the developments, the process.

Since the very nature of utilizing materials such as leaves and botanicals will result in them gradually decomposing in water, and not only changing in appearance, but influencing the water chemistry and physical environment of the aquarium to a varying degree, we as lovers of botanical-style aquariums view every aquarium as an evolving entity.

And, as an evolving entity, a botanical-style aquarium requires some understanding and patience, and the passage of time...

You can't rush this process and expect good results.

As I've mentioned before, when I am establishing a new aquarium, I'm doing my best to facilitate the growth of the microbiome.

A "microbiome", by definition, is defined as "...a community of microorganisms (such as bacteria, fungi, and viruses) that inhabit a particular environment." (according to Merriam-Webster)

Now, sure, every aquarium has a microbiome to a certain extent.

You may not see the organisms which comprise your aquarium's microbiome- at least, not all of them. However, you can rest assured that they are present in almost every aquarium...Especially our natural, botanical-style aquariums.

It's important to at least understand this concept as it can relate to aquariums. It's worth doing a bit of research and pondering. It'll educate you, challenge you, and make you a better overall aquarist. In this little blog, we can't possibly cover every aspect of this- but we can touch on a few points that are really fascinating and impactful.

Many of us are even moving beyond just the pretty look of the botanical-style aquarium, and moving into a deeper stage of understanding how our aquariums function as miniature ecosystems.

Now, one thing that's unique about the botanical-style approach is that we tend to accept the idea of decomposing materials accumulating and remaining in our systems. We understand that they act, to a certain extent, as "fuel" for the micro and macrofauna which reside in the aquarium, and that they perform this function as long as they are present in the system.

When you understand- really understand- this concept, a whole new world opens up to you. Shortcuts and ways to "accelerate" the development of your aquarium have little value to you, because they literally deny you the opportunity to watch your tank evolve.


Aquarium hobbyists have (by and large) collectively spent the better part of the century trying to create "workarounds" or "hacks", or to work on ways to circumvent what we perceive as "unattractive", "uninteresting", or "detrimental." And I think that many of these things- these processes- that we try to "edit", "polish", or skip altogether, are often the most important and foundational aspects of botanical-style aquarium keeping!

It's why we literally pound it into your head over and over here that you not only shouldn't try to circumvent these processes and occurrences- you should embrace them and attempt to understand exactly what they mean for the fishes that we keep.

They're a key part of the functionality.

I've always been fanatical about NOT taking shortcuts in the hobby. In fact, I've probably avoided shortcuts- to the point of making things more difficult for myself at times! Over the years, I have thought a lot about how we as botanical-style aquarium enthusiasts gradually build up our systems, and how the entire approach is about creating a biome-Just like what Nature does.

It works exactly the same in an aquarium...If we let Nature do her work without excessive intervention.

Just be patient. Really patient.

I guess it's tough to be patient sometimes, but I'm really having trouble grasping exactly what the problem is with this approach.

Patience. Again.

Sure, it takes an obscene amount of patience to wait for our tanks to settle in, establish themselves, and be "just right" for fishes.  

So, just let your aquarium settle in for a while- many weeks, if you can- to develop this community of organisms to assist you. Observe what's occurring in your "empty" tank...When you see all of the decomposition, the fungal growth, etc, you can be certain that SOMETHING is going on there. Your tank is coming alive.


I'm telling you, I have just as much fun looking at my "empty" tanks as I do my long-established, fully-stocked ones!

Worrying about the nitrogen cycling process is really kind of foolish, in my opinion. Trying to conceive ways to circumvent natural processes is absurd...Again, ask yourself why this is necessary. Is it because you want to have your tank all ready for "the 'gram?" Because you want to join the "cool kids?"

Resist this hesitation. Enjoy the process. Understand that the nitrogen cycle is not just a "phase"- it's a process- an ongoing one that will function along as your aquairum is in operation. As long as you don't mess with it, or attempt to "circumvent" it. Stop viewing the initial "break-in" or establishment of an aquarium as some sort of barrier be broken on route to something more "interesting." 

Ammonia, nitrite, and nitrate…arghhh! Chemistry. Science. Black and White. Yikes.

Why add chemicals and such to try to speed up this process?

Why not just add organisms to build to your microbiome?

You can add bacteria, however. In fact, this is where our bacterial inoculant, "Culture", can excel. It is comprised of the hardy, incredibly versatile Purple Non-Sulphur Bacteria (PNSB), Rhodopseudomonas palustris.

Like nitrifying bacteria, PNSB metabolize ammonium and nitrite and nitrate. And they're not just important to the nitrogen cycle. They're also capable of aerobic organoheterotrophy - a process of removing dissolved organics from the water column- just like other microbes!

PNSB are useful for their ability to carry out a particularly unusual mode of metabolism: anaerobic photoheterotrophy. In this process, they consume organic wastes while inhabiting moderately illuminated and poorly oxygenated microhabitats (patches of detritus, leaf litter beds, shallow depths of substrate, deeper pores of expanded clay media, etc.).

By competing with other anaerobes and sulfate-reducing bacteria for food, these voracious "sludge-eaters" significantly reduce the production of toxic byproducts such as methane and hydrogen sulfide. Most important- they form a key component of your aquarium's microbiome.

So, yeah, I love these guys as a key part of our little aquarium ecosystems.

Small organisms do HUGE things in our tanks.

It’s important to understand that your best allies in the cause of establishing a new aquarium are bacteria and fungi, as we’ve talked about repeatedly.

Bacteria will arrive in your aquarium naturally through a number of means- on leaves and seed pods, in substrate (particularly if you’re using material from an established one), wood, etc. The nitrifying bacteria that we admire so much are present in almost every aquatic system- even a brand new aquarium. However, there simply aren’t enough of them in a new aquarium to process the waste produced by a significant fish population.  And of course, to grow the population of these beneficial bacteria, you need to supply then with their major energy source- ammonia.

So, what does it mean?

During the so-called cycling process, ammonia levels will build and then suddenly decline as the nitrite-forming bacteria multiply in the system. Because nitrate-forming bacteria don't appear until nitrite is available in sufficient quantities to sustain them, nitrite levels climb dramatically as the ammonia is converted, and keep rising as the constantly-available ammonia is converted to nitrite. Once the nitrate-forming bacteria multiply in sufficient numbers, nitrite levels decrease dramatically, nitrate levels rise, and the tank is considered “fully cycled.”

(A schematic of the nitrogen cycle by one of my favorite mentors, the late, great Bob Fenner!)

So, in summary, you could correctly label your system “fully cycled” as soon as nitrates are detectible (if they are, right?), and when ammonia and nitrite levels are undetectable. This usually takes anywhere from 10 days to as many as 4-6 weeks, depending on a number of factors. Hint- in tanks with a lot of botanical materials in them, this process occurs very quickly. 

Again, what's the rush? You still have your cool, nicely-'scaped tank, filled with botanicals and such, and a developing microbiome. A lot to look at and enjoy...even before fishes arrive in the picture!

Confession: I can't remember the last time I tested for ammonia or nitrite in a new tank. Why? Because the enjoyment of my tank is not predicated upon "getting through" this initial cycle and getting fishes in there as quickly as possible!

So, for arguments sake, let's say you've been dutifully monitoring ammonia and nitrite for the first few weeks in your tank, You saw a little peak and now it's all "clear" to add fishes. We have at least, for purposes of this discussion, established what we mean in aquarium vernacular by the term “fully cycled.” 

Now what?

I mean, is your tank ready to stock with a ton of fishes. Is it"done?" Or is it just on a continuing evolutionary path- one which will result in changes over time, incremental changes in the ecosystem you've established- but one which will keep right on evolving slowly until you either get overzealous with cleaning one day and decimate it, or decide to tear down the tank for some reason.

 Yes, the evolution of your aquarium is a slow, continuous process.  There is no "finish line"- so we need not impose one on ourselves.

In my opinion, the aquarium hobby has created this artificial barrier about the establishment of aquariums. Yes, we have correctly emphasized the importance of establishing the nitrogen cycle in our tanks. However, we have also made it a "barrier" to be broken at all costs, so that we can...do...what?

Add fishes? Sure. But is that the "ultimate" part of establishing an aquairum? Or just one of many enjoyable milestones along the way?

I suggest that you embrace this period of time when your tank is "finding its way" ecologically, and just enjoy the process. Enjoy watching the life forms establish themselves in your little ecosystem. Celebrate the explosion of life which occurs in all new aquariums. Don't take shortcuts to try to circumvent this process. To do so not only risks failure- it denies you a front row seat to one of Nature's true wonders.

Yes, it's a slow, continuous process- an "endless dance"- one that should savored at every opportunity!

Stay patient. Stay observant. Stay curious. Stay educated...

And Stay Wet.


Scott Fellman

Tannin Aquatics


1 2 3 159 Next »