So I have an 8 gallon custom cube with pressurized CO2 from a 5# tank. I have a solenoid with a built in bubble counter. The tubing goes into the tank and is attached to a diffuser with a separate bubble counter built into it. On the CO2 tank bubble counter I have to turn it up quite a bit before I get CO2 into the aquarium. For example, I might be seeing 100 bubbles a minute on the solenoid bubble counter but only 10-15 bubbles per minute on the in-tank bubble counter/diffuser. Is this normal or do I have a leak somewhere? I even removed the inline check valve to see if that was affecting things but no change.