When things like leaves, pinecones and wood fall into a body of water they release a chemical structure called tannins that colors the water.
Tannins are an anti bacterial anti fungal, anti algae agent that works great as a natural healer, supports the immune systems of your aquarium stock and reduces stress! It also lowers pH and KH. They are great for most aquatic life, but especially those that live in Blackwater, low pH environments in the wild.
You can collect leaf litter that release tannins from outside with things like oak and maple leaves, elder cones, drift wood etc. Make sure you confirm what you are trying to collect is safe and that you are far from a road so there is no gasoline residue.
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