If it is Marine Velvet... *Updated*

[MMAX]

I don't think raising the temp will do much for velvet, but get everyone out into a hospital tank. Blennies and gobies are a little moer resistant to things like velvet so I've read, so they just might make it. When I was hit last October, my only fish that showed no signs whatsoever were my lawnmower blenny and my zebra dartfish(goby family). I didn't medicate them, just quarintine. 2 monthe fishless might be a good start, but I went 3 to be on the safe side and everything's fine today.