Help! Clarkii with one eye bulging

[vio]

So this post is on behalf of my father who refuses to sign up for any sort of forum. He has a clarkii clown housed in a 37 gallon aquarium along with a yellowtail damsel, and a scopas tang, 2 fan worms, and a brand new long tentacled anemone. Yesterday was the first day the clarkii would go into the anemone and today we discovered that the left eye of the clown is bulging out. It is not swollen but is bulging. could this be because of an injury, infection, or what?? water quality is excellent NO2-0 NO3-<15 NH3-0 PO4-0 PH-8.2. No other fish show stress or injury and the clown acts normal and eats fine. Could he have gotten stung by the anemone because of lack of resistance from not being in one for years? or is this bacterial related? Any help is appreciated.

[leebca]

The bulging eye could be from any that you listed: injury, infection and add to that stinging by the anemone on top of other stressors.

Anemonefishes are stung by their host, but they have a natural resistance to the effects of the sting. In captivity, some Anemonefishes may or may not be totally able to resist the stinging effects of a strange anemone. Much has to do with how many other stressors there are on the Anemonefish. The more stressors, the less likely the fish can handle the stinging.

In general, the Tang should be removed form the tank. That tank is not good for the Tang which is over 1.5" in length. They need about a 6 foot long aquarium to get up to speed. They travel up to 25 miles a day in the wild and the short aquariums don't serve their need to 'travel.'

Regarding stressors, the Anemonefish is a kind of Damselfish like the Yellowtail, so in essence your father has put two Damselfishes in the same tank. This is a stressor to both, even if we (humans) can't see aggression or signs of negative interaction. Damselfishes are territorial and pretty assertive.

Regarding the current condition: Make a large water change (over 80%) every other day for three times. The low water level will allow for an easy capture of the Tang to find it a new home. Since you'll be making large water changes, follow guidelines here: How to Make a Successful Water Change

If after the third water change there is no signs of improvement in the condition of the eye, OR if during these next 6 days you see the eye bulge out larger or obviously getting worse, then the fish should be removed from the tank, put into a hospital tank and treatment with an antibiotic that goes through the skin of the fish, to fight internal bacterial infections. I like Maracyn Two for Saltwater fishes for this.

So while making the water changes recommended above, go ahead and get a hospital or quarantine tank setup to have it ready.