Re: CO2 Diffuser Incidentally, though I have noticed the manufacturers recommend a minimum pressure of 30psi (2 atmospheres) and they warn that a diffuser may not work at too low a pressure - my diffuser does work perfectly at 1 bubble per 2 seconds, when it is clear of water, or partially filled with water. Have had it working as low as 1 bubble per 5 seconds, so I can't see how that is the cause of the problem I have. At any pressure I suspect that when I switch off the CO2, the water will start back filling the diffuser and tubing. |