NT Labs Aquarium Anti-Parasite eradicates protozoan parasites such as Trichodina, Costia, Oodinium, and flukes which can cause fish to produce a white mucus layer known as velvet or slime disease. Anti-Parasite is a single dose treatment to eradicate these protozoan parasites. This medicine will also kill water snails and invertebrates. Available in 100ml, 250ml and 1L bottles.