The Tint

Ecology first...

Before I ever started Tannin, I grew corals commercially.

As a coral farmer, you're completely attuned to the needs of the organisms you're growing, from both an environmental and ecological standpoint. Before that, I was simply a reefer- a hobbyist who was obsessed with keeping a reef aquariums.

For the first 25 years or so of the reef aquarium hobby, it was all about literally creating a miniature reef- with life at many levels, ranging from invertebrates to corals, and of course, fishes. Techniques, approaches, and gear were developed to foster the development of the overall captive reef environment.

We incorporated "live rock" (calcareous reef rock which has been colonized by all sorts of organisms, from bacteria to macroalage, sponges) into the literal "foundation" of our reef tanks. The rock was a biodiversity catalyst, physical structure, and "filter."

Denitrification was thought to occur in deep layers of aragonite sand, so 3"-5" sand beds were found in almost every aquairum at the time. Procedures and practices all revolved around developing appropriate fauna to help maintain such sand beds. The typical reef aquarium of the early 2000's was a diverse assemblage of all sorts of life. 

And reefs became a lot easier to maintain.

As the hobby evolved, greater attention was paid to the corals themselves- acquiring, studying, and propagating them. 

Suddenly, the "ecology" part of a "reef aquarium" fell to a supporting role, with aquarists spending their time, attention, and money on equipment to provide for the needs of the corals above almost everything else. Sand beds and lots of live rock were seen as less important than mineral supplementation and technical filtration. The high diversity reef tanks of the early 2000's gave way to coral focused aquariums. 

It was about bare bottoms, minimal rock, and lots of mineral supplementation. We discovered that flow was as important , if not more so- to corals than light- so sand was removed, as it blew all over the place under the power of the new pumps we used. Incredible technological advances occurred in pump, lighting,  and other life support equipment, resulting in some amazing gear. Corals flourished.

Because of environmental restrictions imposed by many countries, the importation of live rock was extremely limited, if at all. We began to utilize alternative materials, such as manmade or mined rock, to create our reef structures. It was a necessary, responsible response to the limitations that we had.

There was a certain obsession with limiting nutrients to the aquairum, save those the corals needed.

Corals became almost "easy" to keep and grow. It was the start of a fantastic new era in reef aquariums...

Yet, something was amiss.

You started hearing more and more about "the uglies"- a colloquialism for the phase that a reef tank goes through as it establishes itself ecologically. A phase where algae, biofilms, and dinoflagellates flourished in the absence of competition. A time when cloudy water and bacterial "blooms" were a regular occurrence.

We didn't have these issues- at least, not to such an extent- during the early 2000's, when ecodiveristy and creation of a microbiome were at the forefront of what we did.

It's been that way for a while now. Bare bottom aquariums and inert, artificial rock, as environmentally responsible as they are, create a big challenge in creating a stable reef aquarium.

Fortunately, we're kind of figuring it out, and approaches are being modified to incorporate the development of eco diversity in our tanks using artificial rock. Aquacultured rock is becoming more prevalent, and sand is making a comeback.

Okay, so I'm not including this long-winded description of the last 2 decades of reef keeping just to show you how much I know. I'm talking about this stuff to illustrate the challenges that can arise when we eschew ecology in the establishment of our aquariums.

It's no coincidence that the botanical-method aquarium is a microcosm which depends upon botanical materials to foster the ecology and impact the environment.

This microcosm consists of a myriad of life forms at all levels and all sizes, ranging from our fishes, to small crustaceans, worms, and countless microorganisms. These little guys, the bacteria and Paramecium and the like, comprise what is known as the "microbiome" of our aquariums.

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:

We have the beneficial bacteria which facilitate the nitrogen cycle, and play an indespensible role in the function of our little worlds. The botanical-method aquarium is no different; in fact, this is where I start wondering...It's the place where my basic high school and college elective-course biology falls away, and you get into more complex aspects of aquatic ecology in aquariums.

Yet, 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 broad points that are really fascinating and impactful.

So much of this proces-and our understanding starts with...botanicals. 

With botanicals breaking down in the aquarium as a result of the growth of fungi and microorganisms, I can't help but wonder if they perform, to some extent, a role in the management-or enhancement-of the nitrogen cycle.

Yeah, you understand the nitrogen cycle, right?

How do botanicals impact this process? Or, more specifically, the microorganisms that they serve?

In other words, does having a bunch of leaves and other botanical materials in the aquarium foster a largerpopulation of these valuable organisms, capable of processing organics- thus creating a more stable, robust biological filtration capacity in the aquarium? 

I believe that they do.

With a matrix of materials present, do the bacteria (and their biofilms- as we've discussed a number of times here) have not only a "substrate" upon which to attach and colonize, but an "on board" food source which they can utilize as needed?

Facultative bacteria, adaptable organisms which can use either dissolved oxygen or oxygen obtained from food materials such as sulfate or nitrate ions, would also be capable of switching to fermentationor anaerobic respiration if oxygen is absent.

Hmm...fermentation.

Well, that's likely another topic for another time. Let's focus on some of the other more "practical" aspects of this "biome" thing.

Like...food production for our fishes.

In the case of our fave aquatic habitats, like streams, ponds, and inundated forests, epiphytes, like biofilms and fungal mats are abundant, and many fishes will spend large amounts of time foraging the "biocover" on tree trunks, branches, leaves, and other botanical materials.

The biocover consists of stuff like algae, biofilms, and fungi. It provides sustenance for a large number of fishes all types.

And of course, what happens in Nature also happens the in aquarium- if we allow it to, right? And it can function in much the same way?

Yeah.

I firmly believe that a botanical-method aquarium, complete with its decomposing leaves and seed pods, can serve as a sort of "buffet" for many fishes- even those who's primary food sources are known to be things like insects and worms and such. Detritus and the microorganisms within it can provide an excellent supplemental food source for our fishes!

It's a very interesting  concept- a fascinating field for research for aquarists, and we all have the opportunity to participate in this on a most intimate level by simply observing what's happening in our aquariums every day!

And facilitating this process is remarkably easy:

*Approach building an aquarium as if you are creating a biome.

*Foster the growth and development of a community of organisms at all levels.

*Allow these organisms to grow and multiply.

*Don't "edit" the growth of biofilms, fungal growths, and detritus.

We need to make some mental shifts, always.

These mental shifts require us to embrace these steps, and the occurrences which happen as a result. Understanding that the botanicals and leaves which we add to our aquariums are not "aquascaping set pieces"; but rather that they are "biological facilitators"for the closed ecosystems we are creating is fundamental. These materials are being utilized and assimilated by the organisms which comprise the biome of our aquarium.

Therefore, they are transient. Ephemeral, actually-not permanent.

The key here is that the process takes time. It cannot be rushed. We can, of course, "assist" a little bit, by adding  some bacterial cultures or cultures of other microorganisms, like Paramecium, etc., or small organisms like Daphnia. 

It's a classic way to go in many different types of aquariums, and it's every bit as effective in botanical-method tanks as it is in any other.  It won't help you evade the process by which Nature recruits organisms to develop a microbiome, but it will certainly start the process a little more quickly.

The bottom line is that you need to take time, and go slowly. Your aquarium will evolve over time- regardless of the steps you take (or don't take) to expedite the process. Going slowly- or at least, not doing stuff with the expectation that you'll get to some perceived "destination" quickly- is a great approach.

I'm not in the habit of quoting myself; however, on occasion, something like this little gem from way back in 2016 rings as true today as it did then:

"...regardless of how you employ the botanicals, I cannot stress enough the need to go SLOWLY. There is no need to rush and dump everything in at one time, or in huge quantities. Particularly in an established aquarium, where your animals are used to a certain stable range of parameters...

It goes without saying that if your introducing materials which can influence water chemistry and quality, you will need to go slow and exercise common sense. And, since botanicals are actively "breaking down" in your aquarium over their "service lifetimes", it's important to employ good husbandry techniques (i.e.; monitoring of water quality, water changes, regular filter media changes, etc.)..."

Just some words to the wise, right?

I believe that the idea of embracing some of the things that we’ve feared- like having all of that fungal growth on new wood and leaves and stuff, understanding the turbidity and cloudy water, and accepting the fact that things will evolve past the early, perhaps unsettling aesthetics.

“Pushing through” the earliest phases.

When you think through the idea of how these early impacts are mostly aesthetic, and not harmful to your aquarium, you start to realize that the looks of this stuff ( to many hobbyists, at least) is actually more awful than any possible detriments that they bring. And most important, you'll discover that "editing" it out by removing it from your tank is actually doing damage to a burgeoning ecosystem before it ever really gets off the ground!

If you don't panic.

Do some research, and learn about how natural aquatic ecosystems function, something just "clicks." And you'll understand.

It'll make sense when you get out of your head the notion that you're just trying to go after some sort of aesthetic, rather than trying to nurture the development of a miniature ecosystem within your aquarium.

I think we're starting to see a new emergence of a more "holistic" approach to aquarium keeping...a realization that we've done amazing things so far, keeping fishes and plants in a glass or acrylic box with applied technique and superior husbandry...but that there is room to experiment and push the boundaries even further, by understanding and applying our knowledge of what happens in the real natural environment. 

You're making mental shifts...replicating Nature in our aquariums by achieving a greater understanding of Nature...

And it all starts by placing ecology first.

Stay diligent. Stay observant. Stay curious. Stay focused. Stay patient...

And Stay Wet.

Scott Fellman

Tannin Aquatics  

Grand experiments? Or, just the way our aquariums are "filtered?"

As a lifelong hobbyist, devoted to natural aquarium systems, the idea of outfitting or setting up my aquariums to facilitate biological processes is second nature. With botanicals in play, the concept of them serving as a medium for biological support is "baked in" to our processes.

And you don't need to invest in all sorts of plastic filter media, blocks, beads, "noodles", etc. to facilitate biological filtration in your botanical method aquarium. I use a lot of "all-in-one" aquariums in my work; that is, aquariums with a rear compartment housing the return pump/heater, with space intended to hold biological media.

I run them empty.

Why?

Because the aquarium itself-or, more specifically- the botanical materials which comprise the botanical-method aquarium "infrastructure" act as a biological "filter system."

In other words, the botanical materials present in our systems provide enormous surface area upon which beneficial bacterial biofilms and fungal growths can colonize. These life forms utilize the organic compounds present in the water as a nutritional source.

Oh, the part about the biofilms and fungal growths sounds familiar, doesn't it?

Let's talk about our buddies, the biofilms, just a bit more. One more time. Because nothing seems as contrary to many hobbyists than to sing the praises of these gooey-looking strands of bacterial goodness!

Structurally, biofilms are surprisingly strong structures, which offer their colonial members "on-board" nutritional sources, exchange of metabolites, protection, and cellular communication. An ingenious natural design. They form extremely rapidly on just about any hard surface that is submerged in water.

When I see aquarium work in which biofilms are considered a "nuisance", and suggestions that it can be eliminated by "reducing nutrients" in the aquarium, I usually cringe. Mainly, because no matter what you do, biofilms are ubiquitous, and always present in our aquariums.

We may not see the famous long, stringy "snot" of our nightmares, but the reality is that they're present in our tanks regardless. Inside every return hose, filter compartment, and powerhead. On every surface, every rock, or piece of wood. 

The other reality is that biofilms are something that we as aquarists typically have feared because of the way they look. In and of themselves, biofilms are not harmful to our fishes. They function not only as a means to sequester and process nutrients ( a "filter" of sorts), they also represent a beneficial food source for fishes.

Now, look, I can see rare scenarios where massive amounts of biofilms (relative to the water volume of the aquarium) can consume significant quantities of oxygen and be problematic for the fishes which reside in your tank. These explosions in biofilm growth are usually the result of adding too much botanical material too quickly to the aquarium. They're excaserbated by insufficient oxygenation/circulation within the aquarium.

These are very unusual circumstances, resulting from a combination of missteps by the aquarist.

Typically, however, biofilms are far more beneficial that they are reven emotely detrimental to our aquariums.

Nutrients in the water column, even when in low concentrations, are delivered to the biofilm through the complex system of water channels, where they are adsorbed into the biofilm matrix, where they become available to the individual cells.  Some biologists feel that this efficient method of gathering energy might be a major evolutionary advantage for biofilms which live in particularly in turbulent ecosystems, like streams, (or aquariums, right?) with significant flow, where nutrient concentrations are typically lower and quite widely dispersed.

Biofilms have been used successfully in water/wastewater treatment for well over 100 years! In such filtration systems the filter medium (typically, sand) offers a tremendous amount of surface area for the microbes to attach to, and to feed upon the organic material in the water being treated. The formation of biofilms upon the "media" consume the undesirable organics in the water, effectively "filtering" it!

Biofilm acts as an adsorbent layer, in which organic materials and other nutrients are concentrated from the water column. As you might suspect, higher nutrient concentrations tend to produce biofilms that are thicker and denser than those grown in low nutrient concentrations.

it's pretty much a "given" that any botanicals or leaves that you drop into your aquarium will, over time, break down. Wood, too. And typically, before they break down, they'll "recruit" (a fancy word for "acquire') a coating of some rather unsightly-looking growth. Well, "unsightly" to those who have not been initiated into our little world of decomposition, fungal growth, biofilms, tinted water, etc., and maintain that an aquarium by definition is a pristine-looking place without a speck of anything deemed "aesthetically unattractive" by the masses! 

And then, of course, there are our other rather slimy-looking friends- the fungi.

Yeah, the stringy stuff that you'll see covering the leaves, botanicals, and wood that you place into your aquarium. Let's talk about why you actually WANT the stuff there in the first place.

The fungi known as aquatic hyphomycetes produce enzymes which break down botanical materials in water. Essentially, they are primary influencers of leaf maceration. They're remarkably efficient at what they do, too. In as little as 3 weeks, as much as 15% of the decomposing leaf biomass in many aquatic habitats is "processed" by fungi, according to one study I found!

Aquatic hyphomycetes play a key role in the decomposition of plant litter of terrestrial origin- an ecological process in rain forest streams that allows for the transfer of energy and nutrients to higher trophic levels. 

This is what ecologists call "nutrient cycling", folks.

These fungi colonize leaf litter and twigs and such soon after they're immersed in water. The fungi mineralize organic carbon and nutrients and convert coarse particulate matter into...wait for it...fine particulate organic matter. They also increase leaf litter palatability to shredding organisms (shrimp, insects, some fishes, etc.), which help further facilitate physical fragmentation.

Fungi tend to colonize wood and botanical materials because they offer them a lot of surface area to thrive and live out their life cycle. And cellulose, hemicellulose, and lignin- the major components of wood and botanical materials- are easily degraded by fungi, which posses enzymes that can digest and assimilate these materials and their associated organics!

Fungi are regarded by biologists to be the dominant organisms associated with decaying leaves in streams, so this gives you some idea as to why we see them in our aquariums, right?

In aquarium work, we see fungal colonization on wood and leaves all the time. Most hobbyists will look on in sheer horror if they saw the same extensive amount of fungal growth on their carefully selected, artistically arranged wood pieces as they would in virtually any aquatic habitat in Nature!

Yet, it's one of the most common, elegant, and beneficial processes that occurs in natural aquatic habitats!

It's everywhere.

Of course, fungal colonization of wood and botanicals is but one stage of a long process, which occurs in Nature and our aquariums. And, as hobbyists, once we see those first signs of this stuff, the majority of us tend to reach for the algae scraper or brush and remove as much of it as possible- immediately! And sure, this might provide some "aesthetic relief" for some period of time- but it comes right back...because these materials will provide a continuous source of food and colonization sites for fungal growths for some time!

I know that the idea of "circumventing" this stuff is appealing to many, but the reality is that you're actually interrupting an essential, ecologically beneficial natural process. And, as we know, Nature abhors a vacuum, and new growths will return to fill the void, thus prolonging the process.

You want this stuff in your aquariums.