Damsel not acting right...

[jim mcgonigle]

I have a small tank (soon to be the hospital tank - No LR/LS) that has been running for over 4 months. Its had the same 2 domino damsels in it since day one. One is about 3", the other about 2". Starting Wednesday, the big one has been just drifing around swimming slowly and not eating. It almost appears like its blind. It will take bites at food, but it misses... The smaller one seems fine. There are no obvious visible problems with either fish.
I changed the water again on Sunday just to be sure something weird wasn't going on but I don't think that will help. The Ammonia and Nitrite are 0. Nitrates are around 30ppm, but its been like that since after the cycle. PH, temp and salinity are normal. I also use RO/DI water so that doesn't seem to be a problem.
Ideas?
Thanks,
-Jim

 

[jim mcgonigle]

Anyone?

 

[beth]

How does the fish look otherwise. Swollen gills? Breathing rapidly? What about the fins/tail? Frayed fins? How is the color? Have you noticed any harrassment by the other fish. It is not unusual for damsels to fight.

 

[jim mcgonigle]

The fish looks the same as always. No funny breathing or swollen gills. The fins/tail are fine as well as the color. This is the big one so he usually picks on the smaller one. The small one always runs.
Could he of smashed himself against something while chasing? What else would cause blindness (I'm convinced that he's blind now).
I'm afraid to leave him in much longer, he's not eating and I'm afraid he will really start getting sick.
Thanks.