Firstly, here's my hardware: The CO2 reactor: The filter: It appears that I could be wasting a lot of CO2 using my current configuration as I'm getting gas spurts coming out the filter outlet. The reactor is advertised as being suitable up to 1000 liters and I'm using it on a 180 liter so i would expect it to be highly efficient for this amount. The filter is capable of about 1400 lph which is about whats recommended on this filter. Having met Dan this week and saw how little CO2 he gets through, its opened my eyes that I'm not running efficiently. My current 2kg bottle of CO2 has lasted for about a month while Dan can stretch his for 4 months while maintaining 30ppm. He is using a ceramic reactor into his external filter. My current configuration is as follows: Filter inlet > Filter input > Filter output > CO2 Reactor > Filter Outlet Any ideas on how I can get better diffusion?