Aug 02, 2017 - 01:22 PM
The difference is how much deionized water you will get before having to replace the resin. If you have the large capacity ones you will get more deionized water than if you have the 1 canister. The DIC-20A will provide approximately 300 gallons where as if you go with DI-120 single canister linked below, you only get approximately 100 gallons. Hope this info helps.