Berghia Nudibranch is a ultra specialized animal that only eats Aiptasia. They hunt in packs at least 3 berghias. Do not put them on top of an Aiptasia, always put the berghias on the rock, at dark, so fish don´t mistake them for food. They take some time to eat all of the aiptasias, you might not see them, they go inside the rock holes and are more active at night. Once there is no more aiptasia they starve and die. I wold just give them to a friend or someone in the aquarium comunity that might need them.
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