turn off co2 before light ?

[eminor]

Hello, i have an open top50 liters aquarium, i inject lots of co2, starting 2h before light, i turn it off same time as the light, the drop checker need hours to go back from yelloish to blue, more than 10. Is it possible to turn co2 off 2 hours before the light, will this cause algae ? thx

 

[pat1cp]

I use a plug timer and it goes off an hour before lights out.

 

[hypnogogia]

Hello, i have an open top50 liters aquarium, i inject lots of co2, starting 2h before light, i turn it off same time as the light, the drop checker need hours to go back from yelloish to blue, more than 10. Is it possible to turn co2 off 2 hours before the light, will this cause algae ? thx

Yes, and most people do. Turn it off a couple of hours before lights off.

 

[erwin123]

check the pH difference between (1) CO2 off and (2) lights off. If you are aiming for less than 0.1 variance in pH during photoperiod, and the difference you measure is >0.1, , it means you are switching off CO2 too early.