Well after going back to my normal every other week water changes for just over a month now, I am seeing the same type of tissue damage that I had before i.e. recession from the tips of some (not all) of my SPS. Since it got better with weekly water changes and now coming back with biweekly water changes, the only thing I can think of is that there is something dissolving in my system. I've run poly filter but there is no color change with the exception of the normal browning after a few weeks. I really can't think of anything else it could possibly be. So I'm going to empty my sump (again) this weekend to check for any foreign objects, hopefully I find something as I really don't want to have to do weekly water changes forever :sad2:
Good luck Dan