[FobbyBobby23]

Ditto.

I run my co2 into the intake of my Eheim 2128. 100% diffusion. The first time I set it up, I had a small leak, had to refill in about 4 weeks, now I get several months.

However, now that I mention it, it's roundabout time to switch it out, and I'm out of town...here's hoping it hasn't run out.

Have you had any issues with the impeller on the Eheim? I don't recall if there was ever any conclusive evidence of this, but I remember there are always discussions regarding the possible negative implications of feeding CO2 directly into the intake of a canister filter which would essentially harm the impeller.

But perhaps it is just unfounded paranoia, in that case it would be quite helpful to many individuals (ie those that don't want to spend more money!) in finding an affective method of CO2 diffusion.