How to determine CO2 level

[uklau]

Is there an easier way to determine the level of CO2 without the help of any test kit? Or stick to the rule of thumb of increasing the CO2 level until the fish is gasping for air & reduce it slowly until the fish is comfortable with it?

[valice]

Without test kits, that is one way...
another way is to up till you see pearling within 2hours after lights on, and your fishes not gasping at the end of day...

[PeterGwee]

Base on plant response is one but then that requires a certain amount of plant experience. (Not all plants pearl alot and that varies under different light intensity as well.)

You can consider those long term CO2 test kit similar to that of the ADA drop-checker with a referenced KH solution. Takes some work to make the KH reference solution though.

Regards,
Peter Gwee

[uklau]

Thanks a million, guys.