I have a green BTA that split about three weeks ago. Up until the split, it was huge, vibrant, the tentacles were gorged with water... this thing was THRIVING. Since the split, THEY don't seem as vibrant as they had when it was one. They still have an appetite, and nothing else in the tank has changed. I did perform a water change 6 days ago and can say that I noticed this change in them SINCE the water change. While my test numbers prior to the change were very good, I did the change anyway as I wanted to replenish nutrients consumed by the coral. So I can say I see a connection between the two. The display portion of the tank is 15 gallons and the sump is about another 5 gallons for a total water volume of 20 gallons. When I do a change, I do 5 gallons. Is it possible that I am doing TOO MUCH of a water change? I'm seeking suggestions. Thank you Lyman.