co2 tank? (am i wasting co2)


Lifetime Charter Member
Lifetime Member
Mar 14, 2007
this ? could be looked at a couple different ways. How long does a 10lb tank of co2 last if injecting 25 to 30 ppm of co2 into a 75 gal aquarium? i realize this ? is subjective, with lots of variables, surface movement, light, biomass, o2, ect...( lets assume it's set up correctly.) but also i'm ? ing the efficiency of my reactor.
so if reactor is extremely efficient a 10lb tank in a heavily planted aquarium with med high light could last 4 months? or 5 months? 10 months? really, i dont know? my first 10lb lasted 6 months but i dont think i was getting high enough levels with that reactor. this 10lb tank with a different reactor has lasted 4 months,with better saturation. does this sound about right? am i wasting co2? is there a formula to figure this out? maybe a pole could be taken?
any help or thoughts are appreciated. please chime in. thanks in advance


Junior Poster
Dec 23, 2009
i have mine 5lb co2 tank, 3bps, co2 on for 8-10 hours a day. i haven been using it for last 4 month and still have allot left in it. i think they should last for 6-8 months.