stingray floating alot help!

[Livelife]

I got a 4 inch motoro stingray that was in a LFS for over 3 months eating everything i took him home acclimated over an hour period like i do most fish and added him to the tank. (its a 220) Its been about two weeks now and he eats liek a champ has no problems with any of the other fish (two oscars about 1.5 inches each, a jack dempsey about an inch, two synadotis catfish about 6 inches) hes been eating silversides and shrimp with ease and ive been treating him with live black worms every few days.
Yesterday i saw him starting to "float" near the surface so i checked the water there was 0 signs of ammonia 0 signs of nitrite and mayb 40 ppm nitrate ph was 7.2. I have a wetdry and a fluval fx5 running the tank.

im getting nervouse because right above his eyes is turning like almost white im thinking from being out of the water for a while.

any advice???

 

[keepinfish]

what is your temp? are you sure your test kit is good? sounds like an ammonia spike.

If he is just swimming around at the top that is normal. If he is floating, then you need to start by doing a large water change.

 

[Livelife]

test kits are under 6 months old temp is right at 78

 

[skynoch]

I would have to agree with keepinfish. This is a sign of ammonia in your tank.

 

[vamptrev]

IME top swimming is caused by lack of oxygen or someone on the bottom is picking on him...

 

[Zoodiver]

Can you describe the 'white marks' more for us. Sounds like someone is picking on him.

 

[Iffrat]

mine swims at the top some times .. playing in the outlet of the Fx5 or in the bubbles .. but she also likes to chill on the bottom ..

so if it looks playful it might be ok .. if it looks sick .. it could be bad

 

[Livelife]

its like no color above his eyes where it was out of the water just like white not picking marks just like absence of color

im almost positive no one is picking ive watched at night as well as in the day

i did about a 60 gallon water change and am going to my lfs to get a new test kit and have them check my ammonia

hes now at the bottom kinda curled a bit hes breathing heavy ... none of the other fish are breathing heavy though

theres a wet/dry sump under it 40 breeder so theres a lot of oxygen in the water

thanks for all the help guys

 

[Deaths Sting]

i blame the cichlids.. the eye thing happened to my rays when i through a convict fry into my tank along time ago. cichlids + rays = disaster..

 

[Livelife]

it died : (

it deffentitly wasn't any of the cichlids
plus a convict is way more agressive than a jack dempsey

thanks for the advice again