Red Sea Air Dryer 500 for Ozone & Oxygen Generators. **** PRODUCT MANUAL **** Dramatically increase the efficiency of your ozonizer by adding a Red Sea Air Dryer to its air inlet. Filled with highly absorbent silica beads these dryers remove all moisture from the air before entering the ozonizer. The beads turn from bright blue to an opaque color when filled with moisture. The silica can be easily recharged by drying it in your oven as instructed.