Diffusers, Excellent CO2 dissolve rate. Compatible for aquarium live plants tank. Compatible for pressurized Co2 tanks with at least 2 to 5 bubbles per second injection rate. Not suitable for DIY yeast bottle. Tips: All ceramic disc, tube, or surfaces MUST soaked in water for at least 30 minutes before use. Always wet the glass tubing before inserting the silicon or rubber tubing to avoid damaging glasswares.