Fish swiming at an angle, seemingly aimless

[sudz]

My prized rainbow is swimming very "randomly" and ignoring pretty much everything in the tank.... And then all of a sudden, he'll start nipping at anything that moves. He definately has a "floating" tendancy to him. I would guess it was swim bladder, however, his behaviour change puzzles me. Any idea guys? I can't lose this fish! Hes one of 2 of them, and they were VERY hard to find (Millenium rainbowfish)

Params are all fine. The tank has been at 83-84*f for the last YEAR

I did do a 10% water change the other night, but i didn't have enough dechlorinator... could that be the problem? Should i go run out get some and put some in quickly?

EDIT:

Under closer scrutiny, the rainbow fish seems to have a "scuff" on one of his eyes... the one he swims away from . It does seem to have some fluid underneath, and is popping out slightly. What can i do to fix this? (assuming pop-eye?)

 

[Zagz]

For pop eye you can treat with maracyn or extra water changes. Is he suffering from any bloating? Have you seen him poop lately? Try feeding some frozen peas which will rule out or help with constipation. If there is any bloating you can add some epsom salts to the water. If it is just pop eye, then extra water changes may even be enough.

 

[mom2reds]

I am not an expert but I would do a 50% water change and then use melafix. Most of the time a good water change will help more than anything. From what I have read is that pop eye is a symptom more than an actual disease itself.

Good luck

 

[sudz]

OK, now hes just doing spirals. I tried peas, he couldn't get to them, Hes just.... swimming in circles, upside down and aimless ly. Its pretty... disturbing. He can't tell up from down. Definately a brain thing, i think. What could it be/!?!

 

[Zagz]

He has no bloating at all? If it is neurological there may be nothing you can do. I would try keeping the lights off a bit more to see if that helps at all.