[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: How to maintain high PH/KH with CO2 injection



Roy Cheok <roycheok at cyberway_com.sg> sez:
"The question is....is it possible to maintain a high PH of 8 - 8.5, dKH of >8...in a CO2 injected tank that would be optimal (maybe not quite  optimal...but acceptable) for reasonable plant growth.
Obviously the injected CO2 will tend to lower the PH and KH...etc, but if I maintain sufficient buffers with the addition of sodium bicarbs, magnesium sulphates, borates...etc (with marine KH buffers), can this be done...to have high PH/KH and yet a reasonable concentrated of CO2 in the water.  From the KH/PH/CO2 tables....it doesn't seem to fit  .....but I was just wondering of anyone here has played around with  this before....."

My 20 gallon aquarium has a tiny little power filter (AquaTech 5-15) that I use without filter media to inject CO2 and to maintain water movement.  I filled the filter box with oyster shells, and they slowly disolve to maintain a high hardness and buffer the pH.  I haven't actually measured the kH, pH, etc., but the plants and the fish seem happy.  

BTW, I inject the CO2 24 hours a day without any ill effects on the fish.  The filter's outlet has been adjusted to minimize disturbance of the water surface, and I have a loose fitting glass top covering the top of the aquarium.  The plants start bubbling within a half-hour after the lights come on in the morning.

Best regards,
Bob