CO2 is a PITA
I had it running, but then discovered water was getting sucked out of the bubble counter and into the needle valve, so I had to get a second check valve.
Then I discovered that the tank was empty. From 800 PSI to 0 in less than a month - I checked the connections and found several leaks. Luckily I had a spare tank, so I redid the connections with new teflon tape and that fixed the leak problem. It's finally running, hopefully without any more issues.
yay