API WHITE SPOT CURE works quickly to rid fish of ICH (White spot), cryptocaryon and other highly contagious parasitic diseases and adds slime coat for added protection. Ich, a protozoan parasite, also known as white spot disease, is caused by the external parasite Ichthyophthirius multifiliis. This microscopic parasite has a multi-staged life cycle and is invisible during its theront stage. Theronts burrow into gill and skin tissue causing severe electrolyte loss and gill damage and promoting secondary bacterial and/or fungal infections. Early symptoms of this infection in fish include darting in the aquarium and scratching against the gravel and ornaments. Fish exhibit labored breathing and may remain at the waters surface, near filters and aeration devices. White spots may or may not be visible on fish. WHITE SPOT CURE kills the Ich parasite, usually within 24 hours and is safe for use in freshwater and saltwater aquariums. Corals and invertebrates may be sensitive to this medication. We do not recommend usage in reef aquariums or any freshwater or saltwater aquarium with invertebrates.