Currently, I have 3 female lyre tail Anthias in quarantine. They've been doing well for the last 3 weeks. I chose not to do copper (heard bad stories)....but did prophylactically treat with API general cure - ending the two courses about a week ago. My plan is to keep them in QT for another 3 weeks (totally of 6 weeks)...and then if all is well, transfer to DT. However, during the last week or so, one of the females is starting to be more aggressive.....and keeps the other two "in their corners" by nipping at them. Now, one of my smaller females has pop eye in just one eye. It doesn't look horrible - yet. Im thinking it is most likely caused by trauma..... But....my question is...should I go ahead and treat with erythromycin - just in case? Or watch it to see if it gets worse?