Whole house filtration
Purest Flow X1
One tank treats every drop entering the home. Scheduled backwash, no salt and no brine tank.
What it does
A single-tank carbon filter that treats every drop entering the home. It filters. It does not soften.
- Reduces free chlorine, with granular activated carbon
- Reduces chlorine and chloramines, with catalytic carbon
- Reduces hydrogen sulfide, with catalytic carbon
- Improves taste and odor
- Reduces many volatile organic compounds and selected pesticides and industrial solvents
- Needs no salt and no brine tank
How it works
Contact
Water enters the tank and contacts the carbon bed.
Adsorption
The pores in the carbon capture the targeted compounds.
Delivery
Filtered water continues throughout the home.
Benefits
Whole-home treatment
Water is filtered before it reaches fixtures and appliances.
Media selection
Granular activated carbon for free chlorine, catalytic carbon when chloramines are present.
Improved aesthetics
Helps reduce objectionable tastes and odors.
Softener protection
Carbon upstream of a softener can reduce chlorine exposure to its ion-exchange resin.
Flexible operation
Non-backwashing in/out and automatic backwashing configurations.
Residential sizing
Configurations run from 4 to 10 gallons per minute.
Specs
The simple option. The carbon bed and service conditions do not require automatic cleaning. A best fit for straightforward whole-home taste, odor, chlorine or chloramine reduction when source-water conditions and projected media life support it.
| Reference | Tank | Media (ft³) | Flow (gpm) | Type |
|---|---|---|---|---|
| GACIO9 | 9x48 | 1.0 | 4 | GAC |
| GACIO10 | 10x54 | 1.5 | 6 | GAC |
| GACIO12 | 12x52 | 2.0 | 8 | GAC |
| GACIO13 | 13x54 | 2.5 | 10 | GAC |
| CATIO9 | 9x48 | 1.0 | 4 | CAT |
| CATIO10 | 10x54 | 1.5 | 6 | CAT |
| CATIO12 | 12x52 | 2.0 | 8 | CAT |
| CATIO13 | 13x54 | 2.5 | 10 | CAT |
An automatic control valve periodically backwashes the media bed to lift, clean and redistribute the carbon. A best fit for applications that benefit from automatic bed cleaning, metered water-use monitoring and the potential for extended media service life.
| Reference | Tank | Media (ft³) | Flow (gpm) | Type |
|---|---|---|---|---|
| GACBW9 | 9x48 | 1.0 | 4 | GAC |
| GACBW10 | 10x54 | 1.5 | 6 | GAC |
| GACBW12 | 12x52 | 2.0 | 8 | GAC |
| GACBW13 | 13x54 | 2.5 | 10 | GAC |
| CATBW9 | 9x48 | 1.0 | 4 | CAT |
| CATBW10 | 10x54 | 1.5 | 6 | CAT |
| CATBW12 | 12x52 | 2.0 | 8 | CAT |
| CATBW13 | 13x54 | 2.5 | 10 | CAT |
| Feature | Filter housing | In/Out X1 | Backwashing X1 |
|---|---|---|---|
| Reduces free chlorine | Yes | Yes | Yes |
| Improves taste and odor | Yes | Yes | Yes |
| Reduces chloramines with catalytic carbon | Yes | Yes | Yes |
| Service flow greater than 2 gpm | Yes | Yes | Yes |
| Automatic self-cleaning | No | No | Yes |
| Metered water-use monitoring | No | No | Yes |
| Supports extended media life | No | No | Yes |
GAC is granular activated carbon. CAT is catalytic carbon. Tank sizes are shown as diameter x height. Sizing is approximate and depends on water chemistry and demand.
Source: Purest Dealer Group technical data sheet, rev 09/2026. Final media selection and sizing depend on disinfectant type, source-water chemistry, flow demand, installation and service schedule.
Which homes it fits
The Flow X1 suits homes that want filtered water at every tap. Your water supplier’s disinfectant decides which carbon to use, so the free water test comes first.
Questions about the Purest Flow X1
Granular activated carbon captures contaminants mainly by adsorption and is used for free chlorine reduction, taste and odor, and many volatile organic compounds. Catalytic carbon is enhanced carbon, selected when the water needs more than standard free-chlorine reduction: it also handles chloramines and hydrogen sulfide.
Catalytic carbon. Granular activated carbon is the choice for free chlorine, and catalytic carbon is used when chloramines are present. The final choice depends on the disinfectant your water supplier uses.
The in/out filter is a simple non-backwashing configuration. The backwashing filter has an automatic control valve that periodically cleans and redistributes the carbon, and it adds metered water-use monitoring.
No. It is a filtration system, not a softener, so there is no salt to buy and nothing to refill. Hardness minerals are removed by a water softener, and many homes use both.
Four sizes, from a 9x48 tank with 1.0 ft³ of media at 4 gpm to a 13x54 tank with 2.5 ft³ at 10 gpm. Sizing is approximate and depends on water chemistry and demand.
Book a free water test
A free in-home test shows hardness, chlorine, iron, total dissolved solids and pH before we recommend anything.