Question CO2 injection and sponge filter?

[Subhro]

Hi,
I need help regarding a very basic question. Do I need to turn off the sponge filter when I am turning on the CO2 cylinder? Thanks.

 

[Chanyi]

Ideally you want to run a canister or hang on back filter when running CO2 to avoid excessive CO2 off-gassing. that a sponge filter would allow.

 

[jaydivingboard]

Ideally you want to run a canister or hang on back filter when running CO2 to avoid excessive CO2 off-gassing. that a sponge filter would allow.

Not my thread but I still learned something, do airstones create the same off-gassing problem as well?

 

[Chanyi]

Not my thread but I still learned something, do airstones create the same off-gassing problem as well?

Yes, running increased surface agitation of any kind will "force" CO2 levels back to natural, equilibrium levels (~3ppm).

You can reduce this by increasing the amount of CO2 being dissolved, but it's much easier to control and maintain consistent CO2 levels in a tank using a canister / hang on back filter.