Product spotlight: "Fundo Tropical!"

At Tannin, we're always looking for ideas, products and applications that help you create a real "slice of the bottom" in your home aquarium. Building biotope aquarium displays has become a popular diversion within the hobby, and has proven to be both educations for the hobbyist, and beneficial for the fishes he/she keeps. A win-win!

One of our favorite newer products is what we call "Fundo Tropical", which we offer as a "natural substrate enhancement media." In other words, the stuff helps you create a more natural-looking substrate in your aquarium!

Comprised of clean, natural coconut fibers, this material is easy to work with, and when mixed with more traditional substrate materials, like gravel and sand, evokes the look of a tropical stream bottom, hence its name!

One of the cool things about "Fundo Tropical" is that, once you've prepared it, it lasts almost indefinitely! When you first boil it, it will definitely color the water a dramatic dark brown...probably more brown that you might care for. It leaches a lot of tannins after immersion and boiling, and this will continue for a while.

So, we recommend that you place this material in a large bucket of clean fresh water (RO would be awesome!) to let it soak and leach out more tannins before you add it to your aquarium. Each day, dump out the "soak water" into your garden bed, and refill the bucket with fresh water. This process can take some time- several days, evan a week or two. You need to be patient!  Depending on how much "Fundo Tropical" you are using, and how large the bucket is, eventually, the water will be a bit lighter in color, as most of the initial tannin will have leached out.

 Incidentally, this type of "wait it out" preparation is recommended for almost every botanical we offer. Sure, some will be read sooner rather than later- and some, like Catappa leaves, will start breaking down rather quickly, so you have to use some judgement. As mentioned before, go slow when adding any botanical, so you can gauge the affect on your water quality and most important, the fishes.

When the water is looking a whole lot less dark brown, this is the optimum time to utilize this material in your tank!

You could mix it into gravel or sand substrates, as well as incorporate it into leaf litter and other aquatic botanicals that you might use. It creates a very realistic bottom for many South American fishes, like characins and cichlids, and catfishes, just to name a few.

Now, one of the coolest features of "Fundo Tropical" is that you can use it as a peat moss replacement for spawning of many bottom spawning killifish, including Fp. gardeneri and its relatives, as well as more "annual" species, such as Cynolebias, Austrolebias, Nothobranchius, and Austrofundulus. They readily dive into it as easily as they do peat moss. And, I know some enterprising hobbyists with very understanding significant others, who grind up "Tropical" into a super-fien consistency for breeding, which facilitates the easy removal of eggs from the substrate.


Best of all, this stuff is easy to reuse. Just boil it again and rinse thoroughly, and it's ready for another spawn! So it's economical as well! An added bonus!


All in all, "Fundo Tropical" is a versatile, attractive, and highly useful material that you'll find lots of uses for in the aquarium. I even know of a few customers who use it as a water conditioner, placing some prepared "Tropical" in mesh micron filter bags and installing it in their canister filters. Since this is a far, far more sustainably sourced material than peat moss and other products traditionally used for this and the aforementioned other functions, it's not only effective, but it's ecologically more sound, in our opinion!

If you're looking to rev up your biotope, check out "Fundo Tropical" today!

Oh, and stay tuned for a more "fine grained" version of "Tropical", coming soon! It's that much easier to use as a spawning substrate!

Stay Wet!


Scott Fellman

Tannin Aquatics

Scott Fellman
Scott Fellman


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