Optimum CO2 level for my tank

[booffa]

Hi all,

I've recently setup my pressurised CO2 system and now slowly adjusting the bubble rate. I do not use a solenoid and let CO2 into the tank 24 hours a day.

Stats:

35G tank vol.
heavily planted
Tunze Reg/ Dupla atomiser(diffuser)
CO2 bubbles 1 per 5 sec
Lighting 78 Watts
Lights on @ 11am pH 6.6 kH 5
Lights off @ 10pm pH 7.0 kH 5

The 0.4 difference in the pH between the time lights are turned 'off' and then 'on' because of the build up of carbonic acid does seem to be fine with the fish ( no gasping at all).

Should I leave CO2 at this rate ? Will an increase of CO2 harm my fish?

Thanks.

 

[VaughnH]

When I had a 29 gallon tank running with a ceramic disk diffuser I used about 2 to 4 bubbles per second, and didn't see any adverse effect on the fish. So, I suspect you are still too low on CO2. One bubble per second is what I have noticed several people recommend as a good starting point.

 

[Tom Barr]

The pH should go down slightly, not up after the light peroid.
You are not adding enough. Adjust by adding more slowly.


Regards,
Tom Barr