Everytime I kill my aptasia they come back in a few weeks
. Its the babbies thats hard to kill since its so hard to see them. Gotta be careful when you kill them also cuz they will spour in the water and spread themselves. You can use a kalkwasser rich paste and squirt some on them, just turn off all your flow. Ive got some Blue Life Aiptasia control if you wanna borrow it let me know. Ive used it to kill both manjanos and aiptasia.
You can try some peppermint shrimp but they aren't guarenteed to eat aiptasia. Its hit or miss on them.
You can try the epoxy. Ive never heard of it done though. Let me know how that works out lol. Buy it from home depot so you dont waste your money, its called aqua mend and its reef safe, around 3 bucks