The Iron Breaker III stores a "bubble" of air, compressed by your well pressure, within the media tank. As your water passes thru the air, the iron or sulfur is converted to a particle, which is then trapped by the catalytic filter media in the tank while the air "bubble" is gradually consumed by the passing water. For regeneration, the unit first "backwashes" itself, removing any iron or sulfur particles it has trapped. The system then replenishes the "air bubble" by drawing in atmosphere, temporarily emptying the tank of all water and transferring oxygen molecules into and on the surface of the media bed where all oxidation occurs. The system then returns to the "service" position, again filtering your water.