Due to their tannin content, indian almond leaves (also known as cattapa leaves) are used as a mild antifungal and antibacterial for sensitive aquatic species. Will not harm axolotls, invertabrates or your filter bacteria. Aids recovery from saprolegnia fungus. Also makes a great grazing ground for fish fry and invertebrates. Just add a leaf to the tank and allow it to disintegrate over time. It is normal for the water to aquire a yellow-brown tint. Price is per leaf.