Maya
Aquarium Advice FINatic
We have a condy that our fish never go near. But she seems to be inordinately lazy (as in we placed her on a rock in our tank day 1 and she has never moved from that spot) so I honestly don't know. People talk about how dangerous they are but we have had ours in our tank for 6 months and it hasn't caused us the first problem. I'm sure if it had the chance... It would eat whatever it could? I'm not familiar with the long tentacle anemones so see if someone else offers their opinion on which it might be. If it is expelling large amounts of waste (stringy brown goo), it has recently had a big meal and may be the source of your missing fish.