Evening all, Anyone got any ideas why my drop checker stays green 24/7? CO2 (3bps and in-line diffused) comes on 4 hours before lights on and turns off 30 minutes before lights off. Really good surface agitation, with an eheim surface skimmer and an air pump running for 6 hours overnight. Also running Twinstar M5. With all of the above I’d expect the CO2 to gas off reasonably quickly, but seemingly it doesn’t. I’ve taken the drop checker off the tank and it returns blue. Many thanks in advance.