Waterlife Protozin is a treatment for Whitespot Fungus Velvet and Costia in tropical freshwater and coldwater aquaria. It is used for the control of all protozoan and fungal infections e.g Whitespot Fungus Neon Tetra Disease Velvet Costiasis and Trichodiniasis. You will require 4 separate applications to complete the course of treatment. By adding the treatment on days 1 2 and 3 the product safely compounds in strength and does not burden the already stressed animals with a hard hitting formula. The final dose on day 6 is a preventative measure to try and ensure the organism does not re-occur. Protozins properties are highly effective at treating all its target organisms. Always read instructions carefully before use.