that SAME EXACT thing happened to me less than a month ago!
Here is the thread I started. I got some responses from it. CHECK OUT THE PIC I POSTED!
http://www.monsterfishkeepers.com/forums/showthread.php?t=162258
PUT HIM IN QUARANTINE! RIGHT NOW!
I did and noticed an infestation of worms in the tank. I believed them to be flukes and treated for months and months. I believed the eye to be popeye and treated for months and months. I then noticed that a cloud of something was forming within the eye. I believed this to be an infestation of the worms in the eye. I tried toxic dosages towards the end and endless salt-baths.
I was told that erythromycin and salt was a good cure for the eye issue. If there are no worms present (barely visible to the naked eye, small, white and wriggling around on the glass, appear as a film on tank interior surfaces), then I would give the erythro and salt a shot.
Unfortunately I did not have time to try it.
I thought for sure his eye was going to pop off it never did, one eye was fine and the inflated eye decreased after treating with copper and salt and then Clout.
Soon after treating, both eyes began to fog and swell up. I literally did everything, and spent hundreds on meds. I tried praziquantel products multiple times and could not see any improvement.
Once again, I had
some success with Copper and salt, followed by Clout, and frequent water-changes and dosing. I had some lesser success with some Aquarium Pharmaceutical anti-parasitic meds.
This is just what appeared to work for me and they were drastic measures, so dose and use at your own discretion. My Dat ate till like a blind beast till about 2 weeks before his demise.
I wish you the best of luck, KEEP US POSTED!!! because nobody seems to know much about this problem that effects Dats and it would be great to help others if you came up with an effective way.
Best of Luck!