is a co2 solenoid worth it


Junior Poster
Jan 16, 2008
I am new to planted tanks and intend to get a co2 system with regulator & needle valve.

Any recommendations on companies that make a solid regulator & needle would be appreciated.

Q- Should I also get a solenoid and have the co2 system shut off at night on timer with lights ..... or simply trickle the co2 at a low level 24/7.


Junior Poster
Nov 7, 2007
A selenoid gives me a better piece of mind. I know exactly how to get my CO2 up to 30ppm during the day and I know I'm not killing fish at night. If you're worried about the expense, a solenoid pays for it self if it saves a few fish from being killed. Also, if for some reason you loose power and dont have lighting for a day or 2 the CO2 automatically turns off as well. Automation also makes things easier if you go on vacations and have someone watching your tank for a week.

I have a JBJ solenoid. I've never had a problem with it, but from what I've read some people have.

Tom Barr

Staff member
Jan 23, 2005
I use them.
They work by turning off the CO2 and turning it on only when you want it/need it.

You have no use for CO2 at night, plants don't either.
It certainly does not help fish to have higher levels 24/7.

O2 levels decline as well for fish and having high CO2+lower O2 is not a good situation and gives you less wiggle room.

The cost is relatively minimal from the saved gas, but the dosing can be higher during the day when you need it vs at night when you do not, or forgetful folks not turning the gas tank on every morning etc.

I'd suggest
Clippard solenoids are pretty good, 30$ ain't bad either.

Tom Barr