Indian Almond & Catappa Tree Bark | Terminalia catappa
Catappa Bark Sticks & Tubes on the Surface:
Catappa Bark, often called Betta Bark, comes from the same Terminalia catappa tree that gives the hobby its most studied leaf, and it carries the same high tannin content to match. We offer it in two formats from a single source in Sumatra and West Java, Indonesia: bark sticks, which are thinly cut and easy to break into pieces across the substrate, and bark curls, which uncurl over time into a small natural betta tube. Functionally the two are the same, releasing tannins and humic substances as they break down while providing durable structure, grazing surfaces, and shelter for the Botanical Method, blackwater, and biotope aquarium.
Essential Details
- Tannin Level: High
- Tint Color: Dark yellow to brown
- Durability: High; lasts for months
- Habitat Location: Sumatra and West Java, Indonesia
- Optimal For: Betta splendens, wild-type Betta spp., Apistogramma spp., cardinal tetras and other characins, Caridina and Neocaridina shrimp, kuhli loaches, dart frogs and small geckos in vivariums
- Use with Caution: No known concerns for standard aquarium inhabitants.
- Size Range: Bark Sticks & Curls are 4-6" long
- Quantities: 50g of Bark Sticks or 50g of Bark Tubes per pack
Catappa Bark Sticks & Curls for Aquariums & Vivariums
Once added to the aquarium, biofilm and fungi begin colonizing the rough outer surface of the bark within days. Catappa Bark contains beneficial compounds that bacteria and fungi readily consume, so it is good at cultivating biofilms and the supplemental nutrition that shrimp, bottom-dwelling fishes, and their fry graze as they would in their natural habitat. Its tough fibers create interstitial pore space between the bark pieces, functioning as a structural botanical, contributing its properties over a longer period than more ephemeral materials like leaf litter.
When we allow the bark to condition on the substrate, it releases tannins and humic substances into the water column. These compounds contribute to the organic chemistry of the habitat over weeks and months, gradually shaping the soft, tinted water that blackwater species evolved in. This is a process-driven benefit that develops as the bark matures in the ecosystem, which is why it is best to let it fully break down on the substrate.
The bark curl is shaped for use by the fish themselves. As it relaxes open it forms a small tube that betta fish and other small species use for shelter and spawning, while the flatter sticks settle into the leaf litter bed to add structure and territory boundaries at the substrate level. There is no need to remove either form once it has fully broken down, as the detritus and mulm it produces feeds the network of bacteria and fungi working beneath the leaves in the aquarium or vivarium.
Beneath the Leaves: Terminalia catappa in the Wild
Terminalia catappa grows along tropical coastlines and lowland river margins across Southeast Asia, where it sheds bark and leaf material into the waterways below. That bark settles into the slow-moving blackwater streams of the Indo-Pacific, where cardinal tetras, wild Betta species, and Apistogramma utilize the accumulated litter to forage, shelter, and spawn within it. Its tough fibers cultivate a slightly different assemblage of bacteria and fungi than the surrounding leaves and seed pods, and this material diversity is part of what stabilizes the aquatic ecosystem.
When we add Catappa Bark into the aquarium, we replicate the allochthonous inputs that fuel the food webs of aquatic ecosystems around the globe. Mother Nature leads the way.
Sustainability Note:
This product's packaging is home compostable.
Just like the botanicals inside, it will break down naturally and return to the soil — because what supports your ecosystem should minimally impact our planet.
Not for human consumption. Preparation required.
This is a natural product — variation in color, shape, and texture is expected.
Indian Almond & Catappa Tree Bark | Terminalia catappa
Home is getting more natural
While the aesthetic appeal of botanicals and tinted water can be quite attractive to us, the recreation of nature to emulate water conditions, feeding patterns, spawning displays, and territory building are the true benefits botanicals provide to our critters.
Botanical FAQs
Compostable Packaging Promise
Our packaging is designed to return safely to the Earth, just like the botanicals inside. Every bag is BPA- and Phthalate-free, GMO-free, and contains no animal products. Each meets ASTM D6400 composting standards, ensuring it can fully break down in a home compost bin.
What are the Fluffy White Growths on my Botanicals?
That’s biofilm and fungi—what we call the “goo phase.” It’s one of the clearest signs that your aquarium is alive and functioning. These growths wax and wane naturally as botanicals decompose. They’re harmless, even beneficial, and will disappear on their own once microbial populations stabilize.
Will botanicals lower the pH of my water?
That depends entirely on your source water. In very soft or RODI water, botanicals can gradually lower pH as tannins and humic substances accumulate. In medium to hard tap water, buffering capacity often resists these shifts, and you may not notice much change. At Betta Botanicals HQ, our very hard water (350+ ppm) shows almost no pH change unless we use botanicals like Alder Cones or Macaranga Leaves.
When should I replace leaves or pods in my tank?
We recommend allowing botanicals to fully break down into detritus, since this fuels microbial life and enriches the substrate. You can remove them once they stop tinting the water, but you’ll lose some of their ecological benefits. Each time you add new botanicals, follow proper preparation and observe your livestock until you learn your aquarium’s rhythm.
Are your products just for bettas?
Nope. Our botanicals are safe for almost all aquariums, terrariums, vivariums, and paludariums. The only exceptions are goldfish and axolotls, which may ingest small pods like alder cones or casuarina cones. For those species, we recommend large leaves such as Indian Almond, Loquat, or Jackfruit.
What are Tannins?
Tannins are natural compounds released by leaves, seed pods, and bark as they decompose in water. They soften water, gently lower pH, and create the characteristic tea-stained tint found in blackwater habitats. But their role goes far beyond color—tannins fuel beneficial bacteria, fungi, and biofilms, which form the foundation of a healthy ecosystem. They also offer mild antifungal benefits and help reduce stress in fish by replicating the natural conditions they’ve evolved in. At their core, tannins are plant-derived antioxidants that connect your aquarium to the same processes at work in wild flooded forests and streams.