H2O USRO4-JG 4-Stage Reverse Osmosis System (Faucet Not Included)

The H2O USRO4-JG reverse osmosis system is an under-sink system designed for potable water sources and works best when your feed water falls within these guidelines:

• Water pressure: 45 to 100 psi
• Water temperature: 40°F to 85°F
• pH range: 4 to 11
• Total dissolved solids (TDS): 2000 ppm or less
• Iron: 0.1 ppm or less
• Manganese: 0.05 ppm or less
• Hydrogen sulfide: must not be present

If you are outside these ranges, performance can drop, and filter life can shorten.

This system delivers purified drinking and cooking water from a dedicated reverse osmosis (RO) faucet (sold separately). It includes a storage tank and installation accessories and is pressure-tested before shipping. Choose your production rate (50 or 100 gallons per day) and your post-filter option (GAC or calcite remineralization) based on your taste preferences and household routine.

This system is commonly chosen by homeowners who want better-tasting water for drinking, coffee, tea, cooking, and ice, without relying on bottled water.

• Designed for higher flow delivery after the tank using 3/8 inch John Guest tubing and fittings from the tank to the faucet line.
• Storage tank system means you have water ready when you open the RO faucet.
• Automatic shut-off reduces unnecessary waste by stopping feed water when the tank is full.

What Does 4-stage Reverse Osmosis Mean?

A 4-stage RO system uses four filtration steps to reduce particles, remove chlorine and improve taste and odor, purify with a thin-film composite membrane, and polish the water right before the faucet.

Stage 1: 5 Micron Sediment Prefilter
Helps reduce dirt, rust, and sediment.

Stage 2: 10 Micron Carbon Block Prefilter
Helps reduce chlorine and improves taste and odor, while protecting the RO membrane.

Stage 3: Reverse Osmosis Membrane
Membrane filtration down to 0.0001 microns. Designed to reduce dissolved solids at the ionic level. Typical removal is 93% to 97% of dissolved mineral salts and other contaminants in the feed water.

Stage 4: Post Filter (Your Choice)
Option A: inline GAC post filter for final taste polishing
Option B: inline calcite remineralization post filter to help raise pH and add back a small amount of minerals for a less “flat” taste

Choose Your Configuration: 50 vs 100 Gallons Per Day Output

Choose 50 GPD if:

• You want reliable everyday RO water for a typical household routine
• Your usage is moderate, and you are comfortable with a steadier refill rate

Choose 100 GPD if:

• You want faster tank refill and more available RO water during heavy use
• You regularly use RO water for cooking, beverages, and ice, or you have a higher daily demand

Post filter choice

Choose GAC if:

• You want classic RO taste with a final carbon polish
• You prefer a clean, neutral finish

Choose calcite remineralization if:

• You prefer RO water that tastes less acidic or less “thin”
• You want a more mineral-like taste profile for drinking

What is Included in the H2O USRO4-JG 4-Stage Reverse Osmosis System?

• 4-stage RO manifold with Pentair housings
• 5 micron spun sediment prefilter
• 10 micron carbon block prefilter
• Thin film composite RO membrane (choose 50 or 100 GPD)
• Post filter (choose GAC or calcite remineralization)
• NSF certified quick-connect fittings
• NSF certified metal bladder tank, 3.2 gallons
• John Guest tubing, valves, and accessories
• Automatic shut-off valve to stop the feed line when the tank is full
• Tank ball valve
• Housing wrench and installation parts

Note: RO faucet is sold separately.

Installation

This is a high-level overview. Follow the included instructions for your exact configuration.

1. Shut off the cold water supply under the sink and relieve pressure.
2. Mount the RO assembly where you have service access.
3. Install the feed water adapter on the cold water line.
4. Install the drain connection on the sink drain line.
5. Place the storage tank where it will sit level and remain accessible.
6. Connect tubing from the feed to the filters, membrane, tank, drain, and faucet line.
7. Turn the water on slowly and check for leaks.
8. Flush and start up the system as directed, then discard initial water until the system is thoroughly rinsed.
9. Recheck all connections later the same day.

Replacement Filter Schedule for the H2O USRO4-JG 4-Stage RO System

Replacement timing depends on water quality and usage. Replace sooner if the flow drops or the taste changes.

Component	Typical interval	What to watch for
Stage 1 sediment filter	6 to 12 months	Lower flow, visible sediment
Stage 2 carbon block	6 to 12 months	Taste and odor changes
Stage 3 RO membrane	2 to 5 years	Rising TDS, slower production
Stage 4 post filter	6 to 12 months	Taste changes at the faucet

Warranty information

• RO filter housing assembly: 3 years
• Metal bladder tank: 1 year
• Thin film composite membrane: 1 year

Specifications

• System type: under-sink reverse osmosis, 4-stage
• Output options: 50 or 100 gallons per day
• Tank size: 3.2-gallon bladder tank
• Max feed TDS: 2000 ppm or less
• Water temperature: 40°F to 85°F
• Water pressure: 45 to 100 psi
• Allowable pH: 4 to 11
• Max iron: 0.1 ppm
• Max manganese: 0.05 ppm
• Hydrogen sulfide: must not be present
• Water source: must be potable
• Country of origin: assembled in the USA
• Unit weight: 23 lbs

FAQs on a 4-Stage Reverse Osmosis System

Q: What is the main difference between a 4-stage and a 5-stage RO system?
A: A 4-stage system uses sediment, carbon, a membrane, and a post filter. A 5-stage system typically adds a carbon stage or a specialty stage, depending on the configuration.

Q: Does this 4-stage RO system include a faucet?
A: No. The RO faucet is sold separately.

Q: How do I choose between 50 GPD and 100 GPD?
A: Choose 50 GPD for typical household use. Choose 100 GPD if you want faster tank refill and higher daily demand support.

Q: What does the post filter option change?
A: GAC focuses on final taste polishing. Calcite remineralization helps raise pH and can improve taste for people who prefer a less “flat” RO flavor.

Q: Will a 4-stage RO system work if my water pressure is low?
A: RO works best within the recommended pressure range. If pressure is below the recommended range, production can slow, and you may need a booster pump.

Q: Will a 4-stage RO system reduce chlorine taste and odor?
A: Yes. The carbon stage is designed to reduce chlorine taste and odor, and the post-filter further polishes the taste.

Q: How do I know when to change filters?
A: Replace on a schedule and sooner if you notice slower flow at the RO faucet, taste changes, or reduced production.

Q: Can I install a 4-stage RO system myself?
A: Many homeowners can if they are comfortable with under-sink plumbing and following a step-by-step install. A plumber is a good option if you want the fastest, lowest-risk installation.

Choose your GPD and post-filter option, then upgrade your kitchen with a proven 4-stage RO system that keeps great-tasting water ready for drinking, cooking, and ice.