Hello, I suddenly have the heads of my acan falling out of the skeleton. All parameters are normal for a frag tank. They are in a 30 gal "frag tank". Lighting is 4 bulb t5 and a reef bright blue strip. Temp is stable and auto top off installed. 10 gal water change every 2 or 3 weeks. I use red Sea products and feed reef roids and pemysis. Only a purple tank and 6 line wrasse in the tank for fish. They just ate 2 nights ago (Pemysis), there are blastos and torches in the tank also which look good as normal. The heads almost look over inflated. I am able to catch them floating around in the tank and put them in the mushroom basket in a different tank just because. Any ideas or help would be greatly appreciated.