Thanks folks. I was really worried when it seemed to be spreading to the others. Wanted to frag them, but was waiting till I knew if it was contagious or something. I've noticed similar spots on my live rock and coraline. So now my question is do I need to worry that I'm over dosing with something. I'm pretty cautious about it, only adding small amounts. Well under the recommended for the size of my tank. I test for calcium and iodine, but not mag or iron. Thanks again for the advice.:thumbsup:
