Hi everyone I just set up my new CO2 system and I am using AquariumPlants.com Electronic CO2 Regulator. I have this setup in my 55 Gallon Aquarium and I was wondering what a good second per bubble rate would be. Right now I have it set at around 0.9 seconds per bubble. I need to not worry about PH falls due to my electronic PH regulator (Milwaukee SMS 122), this will turn off my CO2 if the PH falls below my set value. Right now I have my PH set at 7.0 and I probably will change it to 6.8. With my KH at 5 this should give me a CO2 level of around 23ppm 8) So what do you think? Should I lower my seconds per bubble to say 0.5? Any advice on my situation whether it be on the seconds per bubble or PH/CO2 level will be MUCH appreciated! Thanks everyone!!