5 *LARGE* Indian Almond Leaves - Catappa - Shrimp Betta Discus Tannins Spawning. If you are looking to duplicate a blackwater environment, these leaves are perfect, as they will release tannins and darken your water. These leaves have a variety of purposes including inducing spawning in several species of fish, as well as helping soften your water. These leaves also have natural medicinal effects and are beneficial to any softwater fish. Up for sale are Indian Almond Leaves,...