Meanwhile, back in the flooded forest...

If you're a regular reader of "The Tint", you've no doubt seen my posts on some of the many different environments that involve fishes, botanical materials, and blackwater. One of the ones I keep coming back to for inspiration and pure fish-geek study is the "Igapo",  a blackwater-flooded Amazonian forest, which occurs near rivers and lakes. I touched on this in an installment a few months back, and a lot of you wanted a bit more on creating on in your aquarium! Rather than focus on the fishes, which we've done before, let's talk more about the actual environment and some thoughts on replicating it in your home aquarium!

These bodies of water are "seasonally inundated" by the significant rainfall common ottos region; some of these forests may be submerged for almost half a year...that's a LOT of water! Like, 3%-4% of the water in the Amazon Basin at any given time...And these are precious, diverse natural treasures, so replicating one in the home aquarium is another way to learn and teach more about them, isn't it?

Igapo forests have a pretty significant amount of trees; one study found that over 30 species of trees are found in these areas, creating coverage of something on the order of 30%, and are known to have soils that are acidic in nature, yet low in nutrient content (because they don't receive a seasonal influx of nutrients like regions called "varzea", which are flooded by sediment-laden "whitewater" rivers). The water depth can vary from as little as 6-8 inches ( 15.24cm- 20.32cm), to almost 20 feet (6.96m)!  And of course, they have a lot of tannin and humic substances in them from all of the soil and plant materials.

Remember the riparium plant Cyperus that we've talked about before? Well, this species is actually fairly common on the margins of these bodies of water, so you could conceivably create a cool display with this and other riparium plants, to simulate an igapo, complete with the AquaVerdi Riparium Planters...we're just sayin'...

So, getting  back to the subject of aquarium replication of this habitat, it's important to note that you're simulating a forest floor, so take some cues from that habitat to think about things like aquascaping materials and contours. Obviously, there are trees...which you can't really include in at typical aquarium, right? However, you can simulate the trunks and branches of trees with various types of driftwood pieces. In this type of aquarium, I'd tend to favor a darker, denser, "heavier" wood, like Mopani, or the so-called "Amazon Wood" (Azalea root), which gives an overall more "dense" feel than say, Manzanita. And there are no doubt others ("Blackmoor Wood" and so-called "Bog Wood", to name a few). Of course, you can incorporate Manzanita if you want.

As far as arranging the wood, I'd tend to go with a lot more "vertical" orientation, in order to simulate the roots and even trunks of smaller trees. You can "plant" the wood as densely as you'd like it, taking into account the need for circulation, access, and water volume in an aquarium, of course!

And it can't hurt to place a few random pieces i na horizontal position, to simulate root tangles and fallen branches, like you'd see in a rain forest!

For substrate, you can use a variety of materials. Sure, for true authenticity, an acidic soil, such as those used for planted tanks, could do the trick, but since you're really not going to be including aquatic plants in this setup (extremely rare in the "igapo" environment), you're better off, IMHO, using a fine, inert aquascaping sand, perhaps a darker-colored one if available. 

For overall layout and contour, you won't see a lot of variation in substrate depth; however, there are channels and "meanders" within igapo areas that do have some slight buildup of substrate caused by "damming" from fallen branches, etc.  You'd see a little of this on a rainforest floor, of course.A really good way to think about the appropriate underwater "topography", in my opinion, is to look at pictured of a typical rain forest floor.

Even better yet...take some inspiration from our vivarium friends, and literally consider creating the "hardscape" portion of  a vivarium display (without the plants), and then "flooding it" with blackwater. A realistic analog to what actually occurs in nature, right?

(Beautiful vivarium with contour by Shaun Johnson)

Think, for a moment, how materials like leaves, wood, and roots are "distributed" on a forest floor, or in a well though-out vivarium.

(Vivarium pics by Jeff Senske Aquairum Design Group)

As an aquarist looking to replicate this habitat can take comfort in knowing that there are a lot of great vivariums from which to draw inspiration! And, the materials are readily available to create them!


(Vivarium and pic by Sean Elliston)

From a botanical standpoint, you can obviously include leaves...a fair number of them. And I'd go for variety, both in terms of the type of leaves, as well as the sizes...aiming for a mix of small to very large ones!

 Of course, the types of botanicals you could include run the gamut of just about everything that's available. However, if it were me...I'd show some restraint and not go for too much diversity with pods and such.

Rather, I'd limit the variety to say 4-5 types...maybe a half-dozen at the most. This will create a more "cohesive" look and avoid making your display look just too "busy" or haphazard. Remember, the more "permanent" elements, like the wood and sand, should, in my opinion, take precedence over a huge diversity of botanical items, many of which would wash away during periods of inundation in nature, being replaced by just the materials which fall from the tree canopy above. Restraint is good!

The "igapo" habitat can really help you flex your creative muscles, offering the dual challenge of creating something unique, while holding back and not going too crazy with tons of detail. Rather, a fewer, stronger elements, punctuated with some smaller details provided by the botanicals, can create an engaging, mysterious, and inspiring display!

And did we forget to mention, enjoyable? Yeah, that's the key part of the whole thing!

I ope today's brief review has given you a few ideas to help get started. Remember, the diversity of aquatic environments is legion, and there is virtually no limit to what you, the creative hobbyist, can achieve with some time, effort, and imagination!

Stay inspired. Stay resourceful. Stay creative.

And Stay Wet.

Scott Fellman

Tannin Aquatics


Scott Fellman
Scott Fellman


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