The call of brackish water, v. 2.0

As many of you know, our other botanical-style aquarium obsession is brackish water. The most interesting thing about the brackish water aquariums is that the hobby has sort of left it to do...well- not much. And I mean that in a most gentle way, sort of.

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 information on brackish-water habitats from which brackish water fishes come, in the hobby, (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)

Oh, and I can't even begin to tell you the challenge I went through to source a group of Bumblebee Gobies that were actually collected from a brackish water habitat! And even then, the species ID on mine is not 100%; with a few hobbyists insisting that mine are a pure freshwater species...and of course, when I do the research, I discovered that there are populations from both pure fresh AND brackish,,,Arrghhh!

So yeah, what we are faced with, in many cases- difficulty in sourcing fishes, lack of good information on husbandry, and a misunderstanding of the wild brackish habitats, and minimal inspiration from hobby work. Now, I"m not trying to disparage the work that has been done- there have been some beautiful brackish water aquariums, and some articles and such on the topic...but trust me, you have to look good and hard for them!

I say, enough of that!

Okay, I've pretty much poured cold water on the brackish thing, spending 2/3's of this piece outlining why brackish water tanks have sucked for so long..."Gee, great, Scott! That's super helpful, 'Mr. Buzzkill!' How about some positive ideas here?" 


My obsession led me to launch Estuary by Tannin Aquatics- a line within the Tannin brand dedicated to the art and science of brackish water aquariums. When we launched this lien, I knew full well that there would be like 27 hobbyists in the world who would have ebbed a whiff of interest in the topic, and that was just part of the challenge. I realized that, much like when we launched Tannin and attacked blackwater aquariums with a different mindset and approach, it would take tiem to catch on.

And I'm pleased to see that it IS catching on!

Now, first off, the hardest thing we've had to do- and continue to do- is to change the perception among hobbyists that brackish water biotopes are stark white sandy places with a few rocks. Noooooo! Actually, many brackish water estuaries and lagoons are way different than we've portrayed them in our aquariums over the years; They are often turbid, brown-tinted waters, with muddy, rich bottoms covered with decomposing leaves, lots of micro and macro algae, some plants, and often dominated by Palms and  Mangroves. 

And I've heard the "warnings" from people on attempting to replicate this in the aquarium:

"It won't work in a brackish tank! It will create anaerobic conditions! Too much nutrient! Ionic imbalance...Tinted water means dirty!"


Man, this sounds oddly familiar, doesn't it?

Witness the rise of the botanical-style brackish-water aquarium.

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 "tinted" brackish-water aquarium.

Yep, tinted. As in "brown." As in- not your father's brackish-water aquarium. It's not about limestone rocks, quartz sand, and pieces of coral skeleton. Rather, we will use combinations of fine sands, muds, and other materials to create a rich, dark, sediment-filled substrate. Possibly creating higher nutrient conditions than typically associated with brackish tanks. 

Step back from the "doom and gloom" forecasts of naysayers for just a second, okay?

This is not only familiar to many of us I the blackwater, botanical-style aquarium's almost second nature by now!

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. 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.

And one thing that you will love:

The bottom of this type of habitat- and aquairum-is covered with a thin layer of leaf litter. Specifically, mangrove leaf litter. This will not only provide an aesthetically interesting substrate- it will offer functional benefits as well- imparting minerals, trace elements, and organic acids to the water. Mangrove leaf litter, like its freshwater counterpart, is the literal "base" for developing our brackish-water aquarium "food chain", from which microbial, fungal, and crustacean growth will benefit. And of course, these leaves will impart some tannins into the water, just as any of our other leaves will!

And you can play with many different types of substrate materials, ranging from sand to mud and everything in between. 

And then there are mangroves. Not only the live mangrove propagules, which you can sprout in your brackish water aquarium, but the dried mangrove roots and branch pieces, which can create an amazing aesthetic!  And the epiphytic life forms (algae, crustaceans, etc.) which grow on them will perform many of the same functions that they do in nature...


And different.

And wide open for experimentation, innovation, and enjoyment. And the biggest obstacle is the act of forgetting our preconceptions about what this type of aquarium HAS been, as presented to us in the past, and looking at what it COULD be when we try this more realistic approach.

Obviously, we should look at tanks that have been created by other hobbyists for inspiration- and I'll keep putting out pics of my tanks to offer some. Yet, I also encourage you to spend a lot of time looking at nature for your inspiration- observe the nuances, the "dirt", if you will- and the potential for replicating it all in the aquarium.

And the fishes? Well, that will be a challenge until suppliers/breeders/collectors see a demand for them. We're helping to create the market for this stuff, even if we don't look at it from that perspective. And its not just about buying and selling stuff...It's about learning how to care for, spawn, and rear fishes and other animals from this unique environment.

Looking for a new challenge?

Stay excited. Stay innovative. Stay diligent. Stay observant...

And Stay Wet.


Scott Fellman

Tannin Aquatics 






Scott Fellman
Scott Fellman


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