Fish heavy breathing

[Malupoo]

Hey guys,

I have had my tank set up for a while not and have been noticing my fish breathing pretty rapidly and deep.

Tank info-
35g lidless
Temp- 26 degree
Amm- 0
Nitrite- 0
Nitrate- 10-20ppm
Substrate- Eco complete
Pressurised co2
Dose- flourish 3 times a week
Live stock- pair cockatoo apisto, 9x harliquin rasbora, 8x Cory hasbrosus, 1x peppermint bn
Wc- was weekly until last week I now do twice weekly.

History, it's been about 2 month they have been breathing this way it's most noticeable on my cocktail cichlids. But that could be cause they are the largest fish by far and so can see their gills coming right out. Tank is decently planted, I wouldn't say heavily yet.
I have tried everything I can think of at the moment and my lfs is stumped as well. I have now even raised my filter outtake for surface agitation losing some co2 now...

All fish look otherwise healthy and amazing colours it's just the breathing that gets me. Their rate of breath is much faster than my other tank.
What can I be missing.?

Thank you

 

[happygirl65]

What is your water change schedule? It could be too much CO2 so letting the filter splash to gas it off is a good move. You could also do a water change for good measure.

The CO2 is good for the plants but it is possible there is too much CO2 for the plants to use up effectively. I would try turning down the CO2 a bit and do a water change and see if that improves things. I would stop dosing the plants for a day or two while trying to figure out what it is then slowly add things back once the fish are doing well.

 

[Malupoo]

Wc is twice weekly.
Co2 hasn't been going the whole time. I only added it 3 weeks ago. But I have turned it down to less than 1 bubble a second already.