Active Aqua air stones are an ideal way to add oxygen to your hydroponic growing system. The micropore design energizes the growing solution as it aerates and circulates nutrients. Air stones will extend the life of your nutrient solution, help keep roots healthy, and promote exceptional growth. Comes with easy-mount suction cups. Uses 3/8″ ID tubing
 
Model Specs
4" - Standard pressure 0.01 MPa, Max pressure 0.012 MPa. 
8" - Standard pressure 0.012 MPa, Max pressure 0.015 MPa.