Colombian Casho Leaf Litter | Anacardium excelsum
Product Description: Naturally fallen and sun-dried Casho Leaves (Anacardium excelsum) from Colombia. These come from cashew trees growing in the tropical lowland regions of the Colombian jungles. These broad, leathery leaves with textured surfaces and curled forms help recreate the layered complexity of leaf litter beds found across these forest floor habitats for replication in our botanical method aquarium and vivarium. A different species from our Peruvian Casho Leaf Litter, this Colombian Leaf Litter offers a new location for the Biotope aquarist or Vivarist.
In the Botanical Method, Biotope, or Blackwater Aquarium, Casho leaves contribute medium levels of tannins to the water. They are slow to break down, making them ideal for aquarists who prefer a durable leaf litter that supports the microbial food web over extended periods. As they break down, Colombian Cashew leaves promote biofilm growth, offering supplemental grazing surfaces for shrimp, snails, and rasping fishes like Plecos and Otocinclus. Their size and slight curl provide natural shelter for small species like tetras, fostering foraging and territory-building behaviors.
In the vivarium, Colombian Casho Leaves help to create a diverse forest floor that feeds the microfauna, such as springtails and isopods, which we coin as supplemental nutrition, while offering cover for dart frogs, geckos, and other small amphibians and reptiles. Their firm texture holds shape well in humid environments, and when combined with other Colombian botanicals, they help recreate the diverse forest understory found in these tropical habitats.
Our 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.
Quantities: 25-count Casho Leaves from Colombia
Size Range: ~3–9”
Aquarium Botanical Location: Colombia
This is a natural product—variation in color, texture, and shape is expected.
Colombian Casho Leaf Litter | Anacardium excelsum
Home is getting a bit 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.