czieler,
I'm addressing your first/original post only:
Popeye is sometimes mis-diagnosed. Is the
whole eye really popped out from its socket, or is it just swollen in parts or areas around the eye?
Some known causes for the eye swelling include injury (scratched, netting injury, hitting aquarium decor, fight with another fish, etc.) which leads to swelling and may go on to a minor bacterial infection.
Popeye though has three main causes - bacterial, fungal, gas: Usually the Popeye is an outward symptom of an internal, ocular infection either bacterial or fungal in nature. It can be brought on by trauma, bad water quality, and/or a decline of the fish's immune system (e.g., poor nutrition over time) -- the same underlying causes of other symptoms like cloudy eye(s) and even swelling of the eye. Only this infection has affected the ocular area, and goes beyond just a scratched eye or eye surface condition.
The gas condition is rare but does occur. It is essentially when the atmospheric pressure is below the gas pressure in the water. If the aquarium setup doesnââ"šÂ¬Ã¢"žÂ¢t guarantee a fast gas exchange, then there is too much gas in the water compared to the atmosphere around the tank and gas bubbles can form inside fish tissue. The most common event is when you have a pump or device operating (accidently) like a venturi, drawing a lot of air into and mixing with the aquarium water, and that gas is not escaping the water fast enough. Another (albeit rare) phenomena is when a weather front quickly moves in to your area and the barometric pressure drops quickly, and for a short time there is more gas pressure in your aquarium water than in the atmosphere around it and the gas again starts coming out in your fishââ"šÂ¬Ã¢"žÂ¢s tissues. These are both unusual and rare conditions in a small home aquarium systems, but. . .it can happen. What keeps the gas exchange moving along at the optimal rate? It is making sure your tank water surface is moving around so that surface tension doesnââ"šÂ¬Ã¢"žÂ¢t hold back gas exchange. So if you check your equipment and verify you have good water surface movement and a good gas exchange going on, you can forget this one.
Since the ââ"šÂ¬Ã‹Å“true Popeyeââ"šÂ¬Ã¢"žÂ¢ can kill, the fish should be moved to a QT and given antibiotics that will go inside the fish. One such is Maracyn Two for Saltwater fishes. If this doesnââ"šÂ¬Ã¢"žÂ¢t work, switch the meds to an anti-fungal cure (e.g., Nifurpirinol).
If the eye is swollen, scratched or suffered an injury, I would perform a large water change and monitor the fish closely. If the fish is getting proper nutrition:
http://www.reefcentral.com/forums/showthread.php?s=&threadid=785228
AND the water quality and environment is super, the fish should heal on its own. If there are any signs of it not healing or if it gets worse, move it to a hospital tank and begin treatment with an antibiotic (the same as mentioned above).
Since the Popeye is usually an internal bacterial problem, this doesnââ"šÂ¬Ã¢"žÂ¢t spread to your other fish, unless the water quality, environment or nutrition is off.
From your description so far (just your first post) it would seem like an injury. I haven't read other posts, however.
Some threads:
http://www.reefcentral.com/forums/showthread.php?s=&threadid=792631
http://reefcentral.com/forums/showthread.php?s=&threadid=561991
http://www.reefcentral.com/forums/showthread.php?s=&postid=7136521#post7136521
