VIVOSUN Air Stone 2PCS 4 x 2 Inch Large Air Stone for Aquarium, Fish Tank and Hydroponics Air Pump

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Designed to add oxygen and circulate nutrition to your hydroponic growing system.
Extend the life of your nutrient solution, keep roots healthy.
Produce fine bubbles for oxygen replacement.
Size: 4″ X 2″ X 2″. Fits for 4mm inner diameter tube.
Fit for hydroponic systems, ponds, aquariums or fish tanks and other systems.