The air dryer is for use with all Aqua Medic Ozone Generators. The ozone output can decrease dramatically if the supply air is very humid. Ozone Booster should be used to dry the air, especially if a protein skimmer is supplied with ozone using the moist air present in the aquarium cabinet.
In some cases, ozone production can be nearly doubled. The unit uses silica gel as a drying component. The silica gel should be replaced as soon as the indicator beads change color from orange to blue.