When To Do Water Changes Using Pressurized Co2

Dpstriper

New Member
Mar 3, 2019
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New York
I recently added a pressurized CO2 system running at 1 bubble every 3 seconds in a medium to heavily planted 9.2 gallon tank. CO2 is on timer going on an hour before lights go on and off an hour before lights go off. Fish and shrimp are normal and no signs of stress or gasping for breathe. Massive amounts of pearling on plants! My question is when is the best time to do a water change? During the day when CO2 is running or at night when it's off? Does it really matter? Any insight is appreciated. I condition the water with prime and age it for a min of 24hrs. Thanks everyone!
 

toads74

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Jun 3, 2013
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It’s probably not too critical when the water change is done. In a perfect scenario with degassed water, I would do it before co2 comes on, or after the lights go out. Less ideal If you want to you can also just do your water change and leave the light off when you’re done for an hour or so for the co2 to build up again.

My well water comes out of the ro filter with more co2 in it than I’m injecting, so I sometimes just heat it up then straight to the tank after remineralizing.
 
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EdWiser

Member
Apr 16, 2018
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Louisville
I just turn the outlet for the Co2 valve off along with the canister filter and heater. Then do a water change.
It’s not a big deal.