Thanks, I will check out that web site.
I don't really believe the dirty water theory. I have had both xenia and SPS together in same tank for a yr, no problems. My water is pretty good also, no ammonia, trites and low trates, been the same for a yr also. The problem actually started when i indroduced a silver tip xenia into my tank 2 weeks. It completely slothed away first, then the anethilia, and now xenia. No problems with anethilia and xenia in my other tank so far, there was no silver xenia in that tank.