How would I do that?

As you know, we've pushed you time and time again to attempt to replicate natural aquatic habitats, versus someone else's aquarium. And of course, when we're offering up inspiration, particularly for which there is currently no "aquarium facsimile" of, it helps if we give you some ideas about what materials to use to replicate them.

Yes, the very nature of this kind of blog post is a bit overtly commercial, because my best point of reference is the selection of botanical materials that we offer here at Tannin Aquatics. And, despite the fact that this blog is being published in our own website, there is always someone who likes to point out that the recommendations are "slanted" towards our product offerings. (I mean, duh- but yeah, some guys love to point this out).

Obviously, you can acquire materials for your tanks from other sources, or collect some yourself if that works for you. We'd be delighted if you chose to obtain your botanical materials from us, of course...😍

So, obligatory commercial "disclosures" aside, let's get to the idea part!

Let's look at a few interesting habitats, and some recommendations for botanicals that you might want to incorporate into an aquarium version of them!

Flooded Pantanal Grassland

Thanks to our friend, Tai Strietman, we've seen some really interesting and inspiring images of this unique habitat. 

The Pantanal (derived from the Portuguese word "pantano"- meaning "swamp", "wetland", or "marsh") is the largest wetlands region Earth. Full stop. Primarily located within the Brazilian state of Mato Grosso do Sul, it also extends into the state of Mato Grosso, and the nations of Paraguay and Boliva as well! We're talking about region estimated to be as large as 75,00 square miles/195,000 square kilometers!  

It's freakin' huge! 

Essentially a large depression in the earth's crust, the Pantanal constitutes a huge river delta, into which a number of rivers converge, depositing sediments and other biological materials. Now of course, with a habitat this large, there are multiple ecosystems contained in it- as many as 12 have been defined by scientists! 

(Image by Alicia Yo- used under CC BY-SA 3.0)

Now, our main focus is, of course, fishes- and the Pantanal offers plenty of places for fishes to reside in! The cool thing about the Pantanal is that as much as 80% of it is floodplains submerged during the rainy seasons (in which up to 59inches/1,500mm of rainfall have been recorded! That corresponds to water depths which can fluctuate up to 15'/5 meters in some areas!), and is home to an astonishing diversity of fishes and aquatic plants!

With it's enormous expanse of shallow, slowly-flowing water (velocities of no more than 4"/10cm per second are typical), dense vegetation-terrestrial and aquatic- tends to be the norm here. 

The water itself tends to be turbid, and perhaps even a bit anoxic at times. And, interestingly, the highest levels of pH and dissolved oxygen in these habitats tend to occur when the water decreases and plant growth is stimulated. Curiously, however, scientists are not 100% certain if this is because of the plants going crazy with photosynthesis, or mixing of the water column due to influx of water. 

Macrophytes (aquatic plants that grow in or near water and are either emergent, submergent, or floating) supply shelter, food resources and cover for the resident fishes. Still other fishes consume the aquatic insects and microorganisms/biofilms that are recruited in this habitat. Most are well-adapted to the relatively oxygen-poor waters of this vast flood plain.

So, it goes without saying that this is a remarkably complex habitat, with multiple options for replication in the aquarium! I think your first decision is to decide what, if any aquatic plants you'd use. Aquatic plants found in Pantanal habitats include such popular aquarium species as Polygonum, Salviania, Pistia, Ludwigia, and more. You could also incorporate some marginal plants, like Acorus, Papyrus, and other "sedges", to represent the flooded or emergent terrestrial plant component found in these habitats.

Personally, for substrate, I'd utilize a fine sand, perhaps with a powdered form of aquatic plant substrates mixed in. On the surface, you'd certainly want to incorporate some leaves. They're ubiquitous in this habitat. Specifically, leaves like Jackfruit, Guava, and Texas Live Oak leaf litter would work well to represent the appearance and function of the leaf litter component.

In addition to leaves, you could certainly incorporate some other botanical materials, like seed pods. If it were me, I'd be inclined to use a scattering of smaller seed pods, like Dregea, Mokha, and Parviflora - admittedly, none of which are "geographically correct" and actually found in this habitat- all of which replicate the look of the materials found in it, however!

(that whole "Generic Tropical" concept I rant on and on about...)

And of course, with all of that vegetation, you're bound to find some roots, branches, and twigs...So what better way to represent this than with a group of oak twigs scattered about the substrate. Our recommendation, of course, is our "Twenty Twigs" product, which gives you a nice little variety of twigs to fill in some details! You could go with the "regular" or "Large" size, depending upon your preferences.

How would you 'scape your Pantanal tank? 

This habitat is just FILLED with possibilities for replication! You could represent a nice, flat field, or get a little more daring, and do a sort of "shoreline" feature, with sloping substrate, terrestrial, and aquatic vegetation mixed together.

With so few representations of this amazing habitat in the natural aquarium hobby, and see many opportunities to express it with botanicals, it tells me that not only is The Pantanal simply ripe for replication- it's a perfect "ground-floor" opportunity for studying, learning, discovering, and creating evolutions and breakthroughs in the hobby!


Southeast Asia Peat Swamp

Southeast Asia is home to the interesting "Peat Swamps", fascinating and surprisingly diverse in their ecology.

These swamps are important to the local ecology in that they absorb excess rainwater, which keeps rivers from flooding. They are being lost at an astounding rate, as human activity encroaches- and with them, the fascinating fishes- both known and yet discovered- which call these swamps home.  

For example, in the Malaysian Peninsula, it's been estimated that only about 10-20% of the original peat swamps remain. To add to the concern we have, many of the fishes found in these swamps are known to inhabit only certain swamps!

In the well-studied North Salangor Peat Swamp Forest area, it's been estimated that there are about 48 species there, 8 of which have been described to science only within the last couple of decades, and 6 of which are known only from this area.

And that's not entirely unique...that's just one example of many!  


Many of the fishes from these unique environments are classified by science as stenotopic- able to adapt only to a narrow range of environmental conditions. It's been estimated that stenotopic species represent about 18% of the total fish fauna in Malaysia- so to lose these environments would be to lose a significant number of unique fishes!

(Betta livida, another rarity form the Peat Swamps of Malaysia)

One wonders how many of these environments may be lost before some of these fishes are even discovered! Fortunately, there are some governmental agencies in these regions that are making some effort to preserve these unique biotopes before they are lost forever.

So, how would we do this?

Depending upon the species you're wanting to keep, you could probably utilize a relatively small aquarium (like 20 US gallons, or even less) to create a very tightly controlled, cohesive environment. I'd look for a shallow, wide "footprint" for such an aquarium.

Well, obviously, the "tricks of the trade" include utilizing botanical materials to recreate the unique substrate foreign in these swamps- decomposing leaves and such. Now, I'm not one for using peat in our aquariums whenever possible, but this could be a perfect opportunity to use other materials, to create a more realistic substrate.

For example, one could mix some clay-based planted aquarium substrate, along with some of our "Mixed Leaf Media", as well as our  "Fundo Tropical" or "Substrato FIno"- both coconut-based substrate materials- to create an interesting, if not somewhat faithful facsimile of the natural substrates found in these swamps.

Now, in an area which might have overhanging terrestrial vegetation, I'd be inclined to incorporate some Palm-derived materials in any representation of them. I'm thinking about stuff like Nypa Palm pods, Fishtail Palm stems, Coco Palm bracts, etc.

Variousl topes of bark, such as Red Mangrove bark, would perform the dual role of enhancing the aesthetics AND imparting a lot of "tint" to the water via their abundant tannins.

I don't presume to be an expert on planted aquariums, but I do know that some species, such as Cryptocoryne, are found extensively in these environments, and would be the natural and easy choice for plants in such an aquarium. hey do well in rich substrates like the ones we're talking about here.

These plants range from being easy to grow, to incredibly fussy and delicate. And of course, one could make all sorts of arguments about which could be the best to represent this habitat...If you want to research and utilize species which are specific to this habitat, or if you want to use more "generic" choices to represent the species found there...

And of course, being in a forested area, many of these peat swamps have a tangle of roots and branches in them, forming a complete "matrix" which fishes will hide within. Obviously, we have some materials which are appropriate, such as Melastoma root, Malaysian Driftwood, or even Red Mangrove branches, which although not exactly biotope-authentic, are representative of the tangled branches found in these environments.

"Generic Tropical" once again!

Lighting could be subdued, to enhance the swamp-like atmosphere, so you could use LED or T5 with ease. Interesting effects could be created with spot lighting. Filtration would be best accomplished with a canister or external power filter, as water movement is minimal in these swamps. Plus, with a mix of rather buoyant substrate materials, you'd probably want to limit the heavy flow to keep them from blowing all over your tank!

Deeply tinted water. Dark substrates. Aquatic plants. This sounds kind of irresistible to me as an aquarium subject!


Brackish Water "Mangal"

We have been pushing our vision of a botanical-style brackish aquarium for a few years now, and I think it's starting to catch on a bit!

Although aquarists have been playing with brackish tanks for decades, in my opinion, what's been missing is a focus on the actual habitat and how it functions. Just like what the hobby was doing in the blackwater area for years, I think we've been collectively focusing on the wrong part of the equation for a long time- in this instance, just "salt" and basic aesthetics.  

As we've done with most of our work at Tannin, we're focusing a lot of energy on the functional AND ( far different) aesthetic aspects of the brackish environment than has been embraced before.  Our approach to brackish is a little different than the "throw in a couple of rocks and white sand, a few teaspoons of salt per gallon, add some Monos and Mollies, and you're good to go!" concept that you've seen for a long time in hobby literature. It's not quite as sterile and pristine as the world hobbyists have played with before in this sector of the hobby...

 At the risk of sounding like an asshole (lol),  I think that the current "version" of brackish water aquariums is a good part of why they've remained relatively obscure for so long...they are, well...kind of monochromatic, shockingly unrealistic, and dare I say, boring.

Yeah. We won't push "boring" here. You may not like the "tinted, muddy look" we're pushing here- but you won't find it boring!

And of course, there are a few components which, in our opinion, "power" the brackish water, botanical-style system: Mud, leaf litter...and mangroves.

Mangroves are woody plants which grow at the interface between land and water in tropical and sub-tropical regions. Mangroves are what botanists call "halophytes"- plants that thrive under salty conditions. And they LOVE high-nutrient substrates! In many brackish-water estuaries in the tropics, rivers deposit silt and mud, which generates nutrients, algae, and fosters the development of other small organisms that form the base of the food chain. This "food chain" is very similar to what we've been talking about in our botanical-style blackwater aquariums.

The nutrients the mangroves seek lie near the surface of the mud, deposited by the tides. Since there is essentially no oxygen available in the mud, there is no point in the mangroves sending down really deep roots. Instead, they send out what are called "aerial roots" (that's what gives them their cool appearance, BTW), sort of "hanging on" in the mud, which also gives the mangroves the appearance of "walking on water."

And of course, the leaves which mangroves regularly drop form not only an interesting aesthetic and "structural" component of the habitat (and therefore, the aquarium!)- they contribute to the overall biological diversity and "richness" of the habitat. 

Fungi and bacteria in brackish and saltwater mangrove ecosystems help facilitate the decomposition of mangrove material, just like in their pure freshwater counterparts. Interestingly, in scientific surveys, it's been determined that bacterial counts are generally higher on attached mangrove leaves than they are on freshly-fallen leaf litter, and this is kind of interesting, because ecologists feel that attached, undamaged mangroves leaves don't release much tannin, which, as we know might have some ate-bacterial properties. However, it's also been found that materials like humic acid, which are abundant in the mangroves, stimulate phytoplankton growth there. 

Interesting, right?

The leaves of mangroves, as they break down, become subject to both leaching of the compounds in their tissues, as well as microbial breakdown. Compounds like potassium and carbohydrates are commonly leached quickly, followed by tannins. Fungi are the "first responders" to leaf drop in mangrove communities, followed by bacteria, which serve to break don't the leaves further.

Since the mangrove is the "anchor" of the estuary habitat, we will focus on replicating (both aesthetically, and ultimately, functionally) on the root zone of the mangrove tree. This is a fascinating and complex habitat, which serves as a nursery, feeding ground, refuge, and primary habitat for a complex array of creatures. 

We've chosen to utilize mangrove roots and mangrove branch wood for this particular niche, because of its unmistakable aesthetics, appropriate form, and function as a protective area for fishes.

The gnarled, tangled roots of the mangrove tree are the cornerstone of a dynamic, aesthetically attractive aquarium. 

Of course, you can incorporate live mangrove plants into the equation, if you're put to the challenge of maintaining them. These are very slow-growing trees, so you can enjoy them in an aquarium for a very long time by starting with a healthy "propagule" from a mangrove from brackish water.

They need not be "rooted" in the substrate. Rather, they should be secured partially submerged, and they will put down roots as they grow. If incorporated into the dried mangrove roots/branches, you can create a fantastic biotope display!


We like to incorporate specific types of shells in this type of aquarium for their unique and appropriate aesthetics. Specifically, shells which are from representative mullusks that are known to inhabit the mangrove estuaries. We are big on the use of oyster shells to simulate the habitat of the "Mangrove Oyster", Crassostrea gasarwhich adds a realistic touch to the mangrove roots when secured with glue.

For all of the "weirdness" about it, the use of mud and sediment seems to have so many interesting applications, aesthetic nuances, and potential ecological benefits for the aquarium. I love seeing more work being done with various combos of these materials.

Now, my experience with "mud" ( really, "sediments") starts with the reef aquarium world. Mud was one of those odd tangents that hit the hobby right around the “early 2000’s "refugium craze", and sort of faded quickly into the background. I am sure that part of the reason was a renewed obsession later in the decade with less biodiverse, more “coral-centric” systems, which eschewed substrates in general, specifically those which had the tendency to house competing biota!

All of those factors- and a continued obsession with using high tech electronic pumps to facilitate ridiculous amounts of water movement within our aquariums sealed the fate of mud as a true “side show” in the reef hobby for the foreseeable future.

Well, did it? 

Now here we are, in the fading years of the 2nd decade of the new millennium, and I think that it’s time to resuscitate the idea of using mud in our tanks. I know a lot of planted tank enthusiasts have used "mud" in so-called "dirted" planted tanks with much success, and I think there is more to it.

My brackish-water obsession has seen me make liberal use of such sediments, and I'm thinking that there is still much room for experimentation in other types of freshwater, brackish and- yes, reef aquariums.

The combination of dead branches, live mangroves, leaves, sediment, and shells creates a remarkable opportunity to interpret and learn more about the unique mangrove habitats.

One thing that we've done with our mangroves, by the way, is to secure the sprouted propagules to the mangrove branch sections within the tank, with the ultimate goal for them to "touch down" with their prop roots into the substrate. This is a long-term process, as the mangrove is not the fastest-growing plant out there!

However, we play a "long game" and are very patient to let them do their thing and gradually let the roots work their way down into the substrate and for the branches and roots to sprout above the waterline in their own time...

 We are absolutely in love with the idea of "blowing up" brackish water aquariums, which is just great for the hobby!  Our brackish water line, "Estuary," is about three years old now, but really just getting started, and we're all learning some cool stuff together, just like we did in the blackwater world!

Yeah, a little more commercialism in your face, but hey- we want to push this brackish water concept a lot more! 

By not being afraid to go "off-road" a bit, you'll be helping pave the way for others who will follow-just like we're doing with the blackwater, botanical-style aquariums- so that, in the very near future, this type of aquarium will not be perceived by the hobby in general as some sort of "side-show stunt", but just another approach to managing a unique natural aquarium.

It's "open-source", and you're invited to contribute. You'll be helping to "write the code" as they say in Silicon Valley. 

Horrified? Turned off?  Or excited, intrigued, and motivated?

I hope this long-winded, yet frustratingly superficial jaunt into executing on some of the ideas we rant about incessantly around here gives you some practical ideas to execute to replicate some  aspects of Nature in some different sort of aquariums.

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...

You're laying down the groundwork for the next great phase of aquatic husbandry innovation and breakthrough.

Here's to a happy Holiday Season and many exciting innovations in 2020!

Stay healthy. Stay happy. Stay excited. Stay curious. Stay festive...

Scott Fellman
Scott Fellman


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