check valve on output of cannister filter
I'm having some trouble with noise with cannister filter. I have a sun sun 703b, hooked up to rex grigg roughly 24" tall, 2" wide. I've taken it apart, cleaned it, checked the impeller, rocked it to try and get air out. I've primed, and re-primed. Still get that noise like there's air in there. It's not constant, just 10 seconds or so, every other minute or so, just enough to bug me.
So I'm thinking of trying a check valve on the output line between the reactor and filter in case some co2 is running back into the filter.
anybody tried that?
any other ideas?