Help - Cory Swimbladder Problem I Think

[kateyoup]

Hi, can anyone please advise??

One of my cory sterbai's has lost colour around the head and has rolled over a couple of times. He can't seem to keep his balance in the water.

He's pale and slightly red around the gills. Checked the water params -

Ammonia 0
Nitrite 0
Nitrate 8
pH 6.7
Temp 25

I have just done a 30 percent water change. It's a bit strange though to have had the same problem with three different corys from the same batch. Rest of the fish look fine. I'm thinking it must be a swimbladder problem but really don't know now. I've just treated the tank with interpet swimmbladder treatment. Any suggestions anyone? Please!!
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[Tokis-Phoenix]

Sounds like an internal bacterial infection, quite common in cories- is the cories whiskers/barbels all completely intact and there? How often do you feed the cories and what plus how often do you clean the substrate in the tank?

 

[kateyoup]

Sounds like an internal bacterial infection, quite common in cories- is the cories whiskers/barbels all completely intact and there? How often do you feed the cories and what plus how often do you clean the substrate in the tank?

Thanks Tokis. The Barbels are comletely intact. I use a gravel cleaner once a week. He seems to have got worse and is rolling over every time he tries to move. I feed the corys sinking pellets once every second day and occasionally give brozen bloodworm finely chopped up, or freeze dried brine shrimp