I believe my son's tank had a velvet outbreak that decimated all of his stock. Would mela/Pimafix be a sufficient treatment? I've never had to deal with velvet in 30 years of keeping fish. So I'm just scratching my head here. It took out 6 fish in a week, and number 7 is struggling. At first I thought it was a fungus, but now I'm thinking velvet. Funny thing, the ghost shrimp don't seem to be affected one bit.