Looks like it to me, mix some kalkwasser into a paste-like mix, put it in a syringe (use a kids medicine dispense), and squirt it gently into the tentacles. The aptasia will eat it, just watch what happens in 20-30 seconds. I used about 1/4 tbsp on 3 aptasias last night. One has totally disappeared, the other is now a large fleshy bubble. Don't know what that's all about, but I may try to pull it out now.