Branching out: Using Mangrove wood in your brackish aquarium!

With the release of our "Estuary" brackish water line, we've been thrilled to see a lot of you fired up about trying the idea of a  botanical-influenced approach to brackish-water aquariums. It's a logical extension of our blackwater/botanical style approach to freshwater aquarium, and is a unique opportunity for adventurous hobbyists to get in on the "ground floor" of an evolving hobby niche.

And the the excitement over the launch has been incredible! In particular, a many of you have been really excited about the first releases of genuine Mangrove wood, and and we wanted to take a quick moment to explain more thoroughly the different types we offer and how they can be used in your brackish water aquariums for optimum impact!

First off, the wood we are offering is from the Red Mangrove, Rhizophora mangle. Ours comes to us from a trusted source in Hawaii. A lot of you familiar with Mangroves in Florida might think this is crazy, as they're protected there, and removing mangrove wood or other parts of the tree can subject you to fines and other legal trouble. "How can Tannin legally offer this material for sale?" Fortunately for us, the State of Hawaii has designated the Red Mangrove as "invasive" in its waterways, and has made ongoing efforts to remove it. We offer dried wood from the physically removed mangroves. Obviously, "one man's trash is another man's treasure" comes to mind, and we were happy to utilize the mangrove products for more constructive purposes! 

The other neat thing about stuff coming from Hawaii is that the US Department of Agriculture (USDA) is diligent about not allowing pests in our out of the state, and each and every piece is subject to agricultural inspection before it's shipped to us. In addition, only a very limited amount of the exterior bark on some specimens is allowed to pass through, for fear of any pests (insect or otherwise) getting out, so you can have a lot of confidence that your specimens are essentially  "pest free" when you receive them. 

That being said, we still recommend that you give them a nice wash in fresh water, and a careful inspection, just as you would with any piece of wood intended for use in your aquarium. You'll find that, on the whole, this stuff is as clean and safe as any other wood type you've worked with before. You may even want to soak them for a little bit to assure some level of saturation before use.

We offer essentially two types of wood: 

Mangrove branches- These are the actual branches of the mangrove tree, trimmed and stripped of any leaves. Interestingly, if you invert them, you're looking at what is essentially the same "configuration" as the aerial roots the tree sends out, and this is a remarkable, natural representation of the the root for our purposes! Thin, gnarly, and intricate, these pieces are super easy to work with in the aquarium, and will hep you create the "backbone" of what we think is the most authentic-looking mangrove biotope aquarium possible! Some of them are truly large, which will create a dramatic effect in medium to large aquariums. Depending upon the size of your aquarium, the look you're trying to achieve, and the size of the branch(es) you purchase,  you could use a few pieces, or just "one and done!" They are lightweight, and you might need to get clever in securing them into the substrate by weighting them with shells, buttressing them with sand/rock, or even using plant weights.

Mangrove root sections- Just what they sound like- these are thick, woody sections of the prop root of the mangrove tree, and they are cut into little "log-like" sections, varying in both size and thickness. However, they are much, much thicker and more "substantial" in general.  We occasionally get some larger, more "curved" root pieces (premium ones), and these are awesome, too! As mentioned above, the bulk of the bark will be stripped away from these root pieces. They are available in two sizes, "Regular", with lengths of 12 to 18 inches (30.48- 45.72cm) and an average diameter of 1.25 inches (3.17cm)  and "Large", with lengths of 16 to 24 inches (40.64- 60.96cm), and an average diameter of 1.75 inches (4.45cm). You'd use these in conjunction with the thinner branch sections to create a more "complete" look for your habitat. 

Now, Like any wood, there will be some leaching of tannins (although it's less pronounced with the branches than with the root sections, in our experience) and the growth of some biofilms in some instances. This is remarkably durable wood, and lasts a very long time. The branches are extraordinarily flexible, too! 

Far be it from us to tell you just how to use these pieces in your aquarium, but I'd really be remiss if I didn't give you just a bit of advice, right? 

First off, as mentioned above, I'd use the branches in an "inverted" orientation, with the multiple "branchlets" becoming the prop roots of our simulated mangrove habitat. I'd intermingle the branch(es) into a few of the thicker root sections, to give a sense of depth, scale, and structure. To any of these sections, I'd break out the super glue and secure various types of shells to the surfaces. On the submerged sections, you can secure the tiny shells of the Littorina sp. (Mangrove Periwinkle), which look really cool on the roots! 

On the top, above the "water line", I'd incorporate the halves of our small oyster shells , to simulate the habitat of the Mangrove Oyster, Crassostrea gasar. This will create a very unique look in your brackish-water aquarium. 

The interface of the water/roots/substrate is a fascinating ecological niche with tons of aesthetic and functional possibilities. A further enhancement would be to incorporate some live Mangrove propagules into the "matrix" you've created, securing them into the "artificial" root structure, and let them throw down their live roots and create a "living" component to the aquascape.

And of course, a fundamental part of the mangrove ecosystem is leaf litter. The leaves which fall from the mangroves form a part of the food web, which encompasses many organisms, from bacteria to fungi, to mollusks and small crustaceans. By incorporating some dried mangrove leaves into your brackish-water aquarium, you can provide both a functional and aesthetic component which has seldom been embraced before in this hobby segment. We offer two varieties of leaves for aquarium use.

This will impart not only a source of nutrients for the growth of these and other organisms, it will bring a bit of "tint" to the water as the leaves break down over time. Yes, "tinted" brackish water, similar to what you'll see in many wild mangrove ecosystems. This is an entirely new, quite realistic re-imgaining of the captive brackish water ecosystem, something which we have not seen before in the hobby to any measurable extent.

Since we're talking about a lot of organic material in the water, husbandry and attention to nutrient management will be of great importance, and adaptations to filtration, water changes, etc. will need to be made in order to successfully manage such an aquarium. Lots of opportunity here, particularly for those of you with experience from other aquatic "disciplines", like "dirted" planted aquariums, reef tanks, etc. Now, by definition, our system is "representative", as we are incorporating dead mangrove roots. By using some live Mangrove propagules, aquatic organisms, and other organic materials, we can create a more functional representation of the ecosystem.

And of course, there is much more to this...Creating "functional substrates" for brackish-water systems is an entirely new dimension, with all sorts of potential discoveries, challenges, and potential breakthroughs awaiting those willing to take some risks. Creating rich mud-and-sediment-derived substrates is an exciting specialty in and of itself.

Growing plants, crustaceans, mollusks, and fishes in this habitat will provide all sorts of unique perspectives that we can use to gain a greater understanding of the mangrove ecosystem. Much like with our blackwater/botanical-style approach, the "brackish water/botanical-style" system is compelling, evolving, and the perfect "testbed" for advancing the state of the art in aquarium practice. 

We hope that you'll come along for the journey, share what you've learned, and provide valuable input to help bring some much-deserved attention to this exciting, evolving aquatic niche!


Scott Fellman
Scott Fellman


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