Hi crew, I recently purchased a flame angel and placed him my 20 gallon quarantine tank. I was using two Whisper 10 filters. The next morning i discovered what i initially thought to be popeye. However after reading your site i found that if it occurred only in one eye it was likely the result of trauma. Therefore i added some Epsom salt and hoped for the swelling to go down. However, the next day, i found the flame angel to have a clear (air bubble) right above his eye (not on the eye, but more like the eyelid), It seems to be gas bubble disease. However, I’m not sure what may have caused this and what I need to do as far as treatment. I replaced my two whisper 10 filters with a Emperor 280 hoping that the GBD was a result of lack of aeration.