Several weird things going on.....
I have a saltwater tank with 1 domino damsel, 2 yellow tail damsels, 1 six line wrasse, 2 clown fish, 1 hippo tang, 1 lawnmower blenny 1 green chromis.
As I was movimg some live rock around in the tank I noticed a small black spot in the sand. It stunk really bad. I scooped that part of discolored sand out. The next day I noticed the chromis acting strange.... (Dont know how to explaine his actions other than saying he looked like he was humping the rock. ) the same day I found white pimple looking spots on my hippo tang. We went out and got a bottle of api brand super ick cure. We treated it. Waited 48 hours before treating again. The spots cleared up. A day or so later I found a whole area near the glass that appeared over night of the black stuff. The next day I found the chromis and a damsel dead. Did a partial water change tested the water. Everything was perfect. The next day the white pimple spots were back and on all our fish. We took all the live rubble rock out and dosed the tank again with the ick cure.
Is the white spots ick?
What is the black growth in my sand?
What do I do?