Hello. I'm really confused here. I moved a french angel juvenile and a half moon juvenile to a new tank. I used the same rocks, sand and filters. The only new thing I did was purchase I cannister filter to replace the other filters. They were feeding well and then a couple of hours later they had expired. I checked the water chemistry and it was fine except for a pH of 7.76. I'm not sure if this was the reason or not. A few days earlier I had increased the alkalnity to about 4-5 to cushion the pH. The alk usually ran about 3-4. The only behavioral changes I saw was the french angel was scratching against the rocks. I didn't see any obvious parasites. The half-moon was fine. Any Ideas?