Hydra Aquatics CO2 Glass Bubble Counter with Diffuser and Glass Hanger – Pro Series -Made with fine ceramic, to dispense CO2 in mist form -Built in bubble counter -Compact design, durable construction -3 suction cups included -Can be cleaned Hydra Aquatics’ glass CO2 diffuser with spiral tube bubble counter comes with a glass hanger and suction cups. It is best used in aquariums up to 80 gallons. The spiral design allows for better control of the bubble counting. Dimensions: 1 1/4" x 1 1/2" x 4" Instructions: When installing pressure pipes from the CO2 regulator, the pipe should be longer than the distance installed. Open the CO2 regulator slowly. A certain quantity will first accumulate in gauge before starting to dispense. Determine the amount of CO2 required and pH value, add in the adequate amount of CO2 as needed. Important Info: All ceramic discs, tubes, or surfaces MUST be soaked in water for at least 30 minutes before use.