yep. the brown jelly stuff...perfectly happy cup coral. the base, around the edges, turned pink instead of its usual purple and now there is some brown stuff on it. I am hoping it is not the brown jelly that got the goni about a month ago.
If yu believe it is brown jelly, you can give the cup coral a FW dip for about 1 minute. It will kill the protozoans and if it isn't it won't harm the coral, simply make it mad. Make sure you adjust the temp and ph of the FW to match the tank.