“Whole House” Reverse Osmosis for Less than $2500


The usual operating setup for “whole house” reverse osmosis is to allow the RO unit to produce water into an atmospheric (non- pressurized) storage tank and then use a pump to send the water into the home. This arrangement provides a large storage capacity for treated water (300 to 500 gallons is typical for residences). Standard whole house RO units might be capable of producing up to 1000 gallons or more per day to top off the storage tank as water is withdrawn and pumped to the home. Such setups require pretreatment and posttreatment for the RO unit and a shutoff system for the storage tank, plus the re-pressurization pump to deliver water to the point of use.

The system described on this page is a simple RO unit that uses a pressure tank which is very large version of the storage tanks used on undersink RO units. It is designed for use only in small homes — one or two people with low water use–or in other low use applications like offices, medical offices, or large homes with multiple sinks fed by a single RO unit.

This system features a ready-to-use Axeon 300 gallon-per-day RO unit that includes pre-treatment for sediment and chemicals and has carbon post-filtration built in. It is coupled with a high capacity pressurized RO storage tank.  No RO shut-off or re- pressurization pump is needed. The pressurized storage tank sends water to the point of use and the RO unit turns on automatically to refill the tank.

The classy Axeon L1-300 RO unit uses standard-sized housings and membrane for easy replacement. It is a fully automatic unit that shuts off and turns on in response to changes in tank pressure. It is shown here with an optional mounting stand but can also be wall mounted.


Installation consists of connecting the RO unit to the storage tank.  We furnish the tee that joins the tank to the RO unit and sends water to the point of use.  Tanks come in 40, 60, and 80 gallon sizes.



ROMate 80 gallon pressurized RO storage tank. Large fiberglass reinforced RO tanks function exactly like well tanks. Water goes in and out through the single pipe at the bottom. 


Pages with more information:

Axion L1-300 RO Unit.

RO Tanks.