Reminder to check/replace those check valves!
I spent several hours last night troubleshooting my pressurized co2 setup. For some reason I found that no co2 was being delivered to the inline atomizer. Turns out I had not one but two check valve failures at the same time.
One was the Ista check valve between the atomizer and the JBJ style bubble counter. The JBJ bubble counter's built in check valve was also stuck. Neither would open even with 30+psi pushing against it from the regulator.
Ended up replacing the Ista with a generic one. The JBJ's check valve was a rubber piston that you can poke out using a bit of wire. Replaced that with a brass NTP check valve.