Review on Enhancing Oxygenation and Aeration: Clscea 4 Inch Air 🐠 Stone Disc Bubble Diffuser for Aquarium Fish Tank Pump Hydroponics by Jill Weingartner

This air stone arrived well packaged but the nozzles were practically unusable. The check valve let so much air through that it didn't matter how I put it in the line, and the airflow valve came with no air control mechanism. However, the rock has a heavy base, so it will sink to the bottom of the tank with no added weight. The size of the bubbles could be adjusted from very small to larger than the usual small stones found in decorative items.