Okay, so me and my gf bought a cup coral for our 10 gallon nano reef tank. The tank has been set up for almost 2 months and we already had some mushrooms, button pollups, cabbage coral, and star polyps. Well, the cup coral did great the first few days, but then last night we did our weekly water change. Major Problems. Our hairy mushrooms started secreting this nasty purple goo, which we were told was a defense mechinism. Then a few hours later, our cup coral started oozing a huge amount of green goo. It looked as if the pretty blue color of the cup coral was flaking off along with the goo it was emitting. We have NO idea what happened??!! Was it the water change, or the coral ? Our calcium has been perfect and we add purple up and use reef crystal salt. The only thing I could think of was that the alkalinity is always a little higher than normal, but he had been doing so well until the water change. Please let me know what you think.