I never had a problem before, either, but I don’t think you should totally rule it out if you do. I spent a lot of time trying to rule it out only to find it was the likely culprit.
However, your mileage will vary on the need for a CO2 purifier. I needed it; no one else might.
I’m just thrilled that Denny might have learned something from this thread. I’m always learning from him about batch sparging. Thanks, Denny.
Gail