How do I test my co2 levels?

You can download Chucks calculator here:

http://www.csd.net/~cgadd/aqua/art_plant_aquacalc.htm

You need to figure out the KH, DH, and pH of your water. You'll need a testing kit for these. Punch the numbers in the calculator and It'll tell you CO2 saturation in ppm.
 
Just test the Kh(with the kit of course) and test the Ph. Then plug the numbers into the calculator as mentioned above. Dont test at night when the lights are out, or in the morning, wait until the lights have been on a few hours and the plants are kicking out co2.
 
Just test the Kh(with the kit of course) and test the Ph. Then plug the numbers into the calculator as mentioned above. Dont test at night when the lights are out, or in the morning, wait until the lights have been on a few hours and the plants are kicking out co2.

you mean, O2?
 
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