CO2 Diffusers Glass diffusers, inline reactors, bubble counters, and drop checkers. Products Glass CO2 Diffuser L 28 mm Flat Mouth CO2 Indicator Liquid 15 ml CO2 Indicator Glass CO2 Diffuser 28 mm Coil Mouth CO2 Diffuser 40 mm Coil Mouth Professional CO2 Spiral Diffuser Large CO2 Diffusers · Home