I've not added any new zoanthids on to this rock, about 4 days ago I noticed some brown cotton stuff around my green pallies. Today I noticed it has significantly spread the zoas mostly are open and don't seem to care. From everything I'm reading I'm here hydrogen peroxide dip is where it's at I'm just scared to take that rock out and dip it if it's not something bad... It's hard to get a picture so I uploaded a video I hope it helps anyone please help..
brown cotton around zoanthids
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