10/15/2026
is our day of rewriting the worries that surround detritus in our Botanical Method, Blackwater, and Biotope Aquariums. Vilified for supposedly causing excess nutrients in the ecosystem for nuisance algae, this is often new aquarists’ point of friction for embracing the method. 🍂🧵👉
The source of where this detritus originates from is what matters most. Detritus formed from uneaten fish food and fish waste is chemically and compositionally different from the detritus that forms from naturally fallen botanicals. Fish Food and waste are high in nitrogen and the minerals needed for both plants and algae. Not all algae is bad, as some amounts are always present in our fishes natural habitats and are consumed by microfauna or our fishes directly.
When naturally fallen botanicals enter aquatic habitats either via seasonal inundation of the forest floor or fallen from the canopy above (both allochthonous inputs!), these leaves have had their nutritive properties pulled out of them by the plant, leaving behind cellulose, lignins, tannins, and humic substances, with comparably low amounts of nitrogen/vitamins/minerals. Detritus from botanicals is Fuel. Feeding beneficial fungi and bacteria beneath the leaves.
They use cellulases, hemicellulases, and ligninases to break down hard-to-digest plant structures like cellulose, lignin, and wood fibers.
The fish, bacteria/fungi, detritus food chain is important in nature as fish forage on this beneficial bacteria/fungi, as supplemental nutrition and consequently ingesting detritus as they feed.
Putting this into practice in our Botanical Method Aquariums hinges on our water change schedule and siphoning practices. When we remove detritus, we remove a layer of the food web… “someone else’s food”. So if you MUST remove some detritus, 10% or a 3x3” square on your substrate to expose the substrate below (except detritus IS substrate if you think about it!) for the visual appeal of the ecosystem to us, the human, is okay. But do not remove too much! Leaf it be!
