Review on 🐠 VIVOSUN Air Stone: 2PCS 4 X 2 Inch Large Air Stone for Aquarium and Hydroponics - Boost Your Pump's Performance! by Katie Bowers

I can only speak for hydroponic applications, DWC pumps at 950 gallons per hour (enough power). I have 6 of these and they all pale in comparison to the smaller round air stones. They just blow big bubbles from above and at a very slow speed. I tried 6 different Airstone designs and this one came in last. You don't have to epoxidize it to make it work well, that's ridiculous. Their only advantage is that they stay in place due to their weight. I found a much better weighted one that is hemispherical and works much better. Not recommended for hydroponics