Catappa Leaves are commonly used amongst aquarium owners because they have many positive effects on your home fish tank. Many people use them to help condition their water, removing heavy metals, releasing natural tannins and lowering the PH. They have also been used to help promote spawning in shrimp and other aquarium creatures. They have been known to also have mild anti-fungal and anti-bacterial properties. The leaves will naturally water log after 1-3 days, and can remain in the tank until almost completely dissolved. Catappa Leaves will release natural tannins. Rinse well, or boil to help reduce amount of tannins released. Use smaller portions of a leaf if being placed in smaller tanks or Betta bowls.