I know this question was asked several times already but I couldn't find a clear answer to my question. I am back from saltwater and after some thinking I decided to have nee tank built with an overflow. I initially thought about connecting eheim canister filter to a durso pipe but I read there may be air trapped In canister stopping the flow. I am going to have an ato controller on the tank but still would like to have a fail-proof system. So back to a drawing board and I thought of coming back to using a sump. Question is: how much of an outgassing will I face by using a sump? I don't mind if I have to up my bubble count slightly but will it still supply enough co2 for my plants? The tank will be around 90g and I am not planning to seal the dry portion. I also would like to use an either cerges or gregg style reactor? What do you think about that idea?