Recently we received an email asking a question we wish more people would ask… so they can save themselves a lot of grief, and in some cases, a lot of money!

Do I need to clean my reverse osmosis filter?

Given that many reverse osmosis systems use a tank to store water for use after filtration and the water, once it enters the storage tank, contains no sanitizers or disinfectants to prevent growth of ‘biologicals’ (aka: slime on internal surfaces)… Yes, you will want to clean out, at a minimum, the storage tank every once in a while. Consult your owner’s manual for specific instructions and cleaning intervals.

Most likely your manual will suggest the use of a Sanitizer Concentrate which contains chlorine. Below you will find examples of products for this application:


Single Pack


24 Pack

(General) Instructions for Use:

Water Softener Application: Mix the 1/2 oz. Packet of Sani-System with 4 gallons of water and then pour into salt tank. Manually regenerate the softener. Double the dosage for heavily fouled units.

RO ( reverse osmosis ) Units: Turn off RO system, drain storage tank and remove all filters and membrane. Pour 1/2 ounce Packet of Sani-System into the empty pre-filter housing. Reconnect and turn on incoming water. After the holding tank is full ( takes about 5 minutes ), let the system stand idle for 60 minutes. Drain Holding tank. Before the system is put back into service, flush the system with water to assure sanitizing solution is rinsed thoroughly from system. Re-Install filters and membrane occurring to manufacturer’s instructions. ( source )

The directions above serve as a general guide for use of the cleaning product. Please remember, though, to make sure you follow the directions outlined in you water filter’s manual for best results!