Found a spooky alien tentacle thing in my tank

[Tonedeafviolinist]

Is it a dead aptaisia, or something worse? I'm currently treating the tank with prazipro for ick, so maybe whatever it is died from that. I haven't gotten any new livestock or rocks in over six months, so I don't know where it could have came from.

 

[Angelwolf21203]

Aiptasia? Yes. Dead? No.