Complete co set for aquariums up to 100 litres. The pressure regulator controls the amount of co flowing into the diffuser. Inside the diffuser, the built-in bubble counter allows you to see how many co bubbles are released in a given time. The diffuser produces very fine bubbles so that the co gas is well absorbed by the water. With the adaptor available as an accessory, you can upgrade this set and use a large 800 or 1200-gr co2 cylinder.. The co advance set consists of:. 95 Grams co pressure cylinder. Pressure regulator. 3-In-1 diffuser connections.. Please click here for instruction manual