Hydro Flow Octa-Bubbler 20 GPH Flow Control Device - Green (8/Bag)
Octa-Bubbler? flow control device allows you to change the gallons per hour on your Octa-Bubbler? without replacing it. The flow control devices are color coded. Choose the red flow control device for 10 GPH, the green for 20 GPH and the black for 6 GPH.