I have a RTBA, it looks great. Nice color, it's grown in size in my tank. My pH 8.2-8.3, sg 1.026, NH3=0, phos=0, trates 20ish. I've had it around 8 months. Today I saw one of the tentacles come off. I see no signs of injury. It looks normal. The mouth is normal, the foot looks normal...