PuROTwist 4000 RO System Review

The PuROTwist 4000 is a top-selling Reverse Osmosis water filtration system because its quick-connect filters make it very user-friendly. The four-stage, point-of-use RO system treats water at 50 gallons per day and is easy to install under the kitchen sink. It has become increasingly popular because it is easy to install and maintain with twist-off-and-on filters.

Pros of the PuROTwist RO System

User Friendly: Filters are easy to replace with twist-off, quick-change filter design.

Plenty of Water: RO system comes with a standard 4.4 gallon storage tank, providing plenty of water for a large family or frequent cooking needs.

ANSI/NSF Standards: Conforms to ANSI/NSF standards 58 for performance claims as verified and sustained by test data.

Economical Replacements: The availability of cost-effective replacement filters can help to keep ongoing maintenance costs low.

Outstanding Taste: Removes impurities such as sediment, lead, VOCs, chlorine and more for enhanced flavor of drinking water.

Cons of the PuROTwist RO System

Faucet type: Comes with standard chrome faucet. When making purchase, must select air gap or non-air-gap faucet.

Fewer Filtration Stages: The system includes four stages of filtration instead of five stages.

Required Maintenance: Filter housings should be cleaned at time of filter changes.

Flow Rate: Water flows through 3/8" tubing to the faucet.

Quick Look at the PuROTwist 4000 RO System

The PuROTwist under-sink RO system has been a popular, high-performing system for many years.

1. 1. The PuROTwist 4000 RO system features "quick-connect" filters to make filter changes fast and easy. No tools, buckets or mess required.
  2. With four stages of filtration, the PuROTwist can significantly enhance the taste, odor, and overall quality of your drinking water by removing up to 99% of impurities and pollutants including Barium, Cadmium, Chlorine, Pesticides, Chromium VI, Copper, Fluoride, Lead, Mercury, Nitrate, Radium, Selenium, TDS (total dissolved solids)
  3. This point-of-use reverse osmosis system is manufactured in the U.S.A.
  4. The PuROTwist has an automatic shut-off feature which signals the system to stop making water until more is needed.
  5. High-capacity filtration produces 50 gallons of water per day, which means you'll have plenty of drinking water for your family or cooking needs.

Benefits of PuROTwist RO Filtration System


Easy to install and maintain	Clean, filtered water convenient at kitchen RO faucet
Better-tasting soups, sauces and meals	Environmentally friendly - requires no chemicals
Delicious, fresh drinking water	Saves money over buying bottled water
Quality water for your aquarium	Clear, harder ice cubes

PuROTwist 4000 RO System

PuROTwist 4000 RO water filter system offers the highest of quality and performance standards.

The high-capacity (50 GPD) reverse osmosis system features quick-connect filters that make it easy to change out filters. To replace the filters, simply twist the used filters off, and twist the new filters on. No tools, no bucket or mess. The system's automatic shut-off feature signals the RO unit to stop making water until more is needed.

The PuROTwist 4-stage, point-of-use RO system features a compact size for simple installation under your kitchen sink.

PuROTwist 4000 RO System FAQs

Which replacement filters do I need for the PuROTwist 4000 RO system?

The PuROTwist 4000 RO system takes Ominipure Q-series filters. Their twist on/twist off style makes filter replacement easy. While the system's three filters should be replaced every 6-12 months, depending on water quality and household usage, the RO membrane only needs to be replaced every two years. Our replacement parts page for the PuROTwist 4000 includes the filter kit with just the 3 filters, or the complete filter kit that includes the RO membrane.

Is the TFC-400 easy to install?

Yes, the installation of the TFC-400 might be considered easier than other RO systems as it has fewer tubing connections. We provide general RO installation instructions here. And you can review the TFC-400 installation manual here.

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