looks to me like a snail or something walked over it, if the problem is still there in a day or two then it could possibly be something else, i got zoas that do this frequently when either my hermits or snails go over them or they get sand in them so they do it to clean themselves.
Could B worms cause this by crawling on them? Other then that I can't think of anything. I have no crabs, they were high up on LR, next to nothing. I'm so freaking bumbed
I'm actually this close | | to giving up on zoas.
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