Under Sink Filtration System | RO-400

Experience Our Top Selling 5 Stage Under Sink Filtration System – Giving You Taste Similar Crystal Geyser©. Very popular among those who are concerned with removing Chloramines and Fluoride – it is no longer and issue with you – you have already decided that you want water that is as Chemical-Free as possible. The RO-400 Uses All WQA and FDA Certified components, and is engineered to remove the widest spectrum of contaminants of any reverse osmosis system, due to its enhanced filtration, such as:

  • Arsenic
  • Asbestos
  • Barium
  • Bacteria
  • Cadmium
  • Chlorine
  • Copper
  • Cryptosporidium
  • Cysts
  • Fluoride
  • Giardia
  • Hexavalent Chromium (6)
  • Lead
  • Pesticides & Herbicides
  • Prechlorate
  • Radium 226/228
  • Selenium
  • TDS
  • Toxoplasma/Entamoeba
  • Trihalomethane (THM)
  • Turbidity
  • VOC’s


Elite 5 Stage Filtration – Intense Filtering Starting Out With Basic Sediment and Minor Particle Removal & Ending in A Secondary Activated Carbon Disinfection To Rid of All Tastes. 

  • Stage 1 – Carbon Block Filter Removes Sediment, Chlorine and Other Chemicals
  • Stage 2 – Enhanced Chloramine Reduction Cartridge Also Removes Chemicals
  • Stage 3 – Enhanced Fluoride Reduction Cartridge
  • Stage 4 – Reverse Osmosis Membrane: This stage gets rid of dissolved substances including radium, lead, arsenic, and many others.
  • Stage 5 – Quantum Disinfection™ and Granular Activated Carbon Final Polishing Filter Kills Bacteria and Enhances the Taste of the Water.

Got a Question Regarding the RO-400 or need a quote? Call 310-894-8488 to speak to water filter technician now!




  • A Convenient Under Sink Filtration System: With a Grain Capacity of 50GPD, it’s customized for individual homes, offices, and small business with easily under sink storage.
  • State of the Art Reverse Osmosis Filtration giving you “Nestle Bottle Water” quality coming out of your kitchen faucet.
  • TFC Membrane Technology: Bacteria resisting membranes that have a higher removal rate of total dissolved solids compared to CTA membranes (frequently used by our competitors).
  • High intensity 5 Micron Sediment Filtering.
  • Designer faucets available in a variety of colors and styles.


  • All Components are FDA & WAQ Compliant or Certified
  • Full 3/8″ Flow From Tank-to-Faucet
  • Deluxe 3/8″ Tank Valve
  • Deluxe Inlet Valve
  • All-American Made Filters and Membrane
  • 3-Year Warranty
  • Upgraded Designer Faucet in Choice of Two Colors
  • 4.5 Gallon Tank
  • High Pressure Permeate Pump Upgrade Option For Houses With Ice Makers, Multiple Outlets, Or Installations In Basements, Garages, and Mechanical Rooms
  • Standardized Purification Formula and Enrichment Combination, Wielding 5 Stages of Standard Purification


Manufacturer’s Warranty: 3-Year Warranty (excludes filters, membrane is pro-rated)

Installation Warranty:  Praz warrants to the original Customer that installation work performed by Praz for home water softeners for homes & houses, commercial water softeners, Industrial Water Softeners, Commercial Under Sink Filtration System, and Alkaline Whole House Systems, and water conditioners will be free from defects in workmanship for a period of 3 years from the date of installation, subject to the terms and conditions contained in this warranty document. Praz will perform the installation services in a professional manner and in substantial conformance with the manufacturer’s installation instructions.

Praz’s warranty is limited to correction of any defective workmanship at no additional cost to Customer. This warranty covers installation services provided by Praz. Please consult the product warranty provided by the manufacturer for warranty coverage of products.

This Limited Warranty does not cover any defects or damages arising from causes other than the defective performance of the installation services provided by Praz, including but not limited to Customer’s failure to observe manufacturer’s instructions with respect to the product, subsequent alterations, misuse or abuse of the Praz installed product, or other causes beyond Praz’s reasonable control.

VOIDED WARRANTY: This Limited Warranty is voided if the product is removed, repaired, re-installed or otherwise tampered with.

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Why Choose Praz

A few reasons why we stand out…
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Platinum Service

As a locally owned business, we take pride in every one of our customers. Flexible payment options, free in-house quotes, and frequent “check-up” calls are just few of the ways we try to maintain our relationship. When you contact Praz, you are not forwarded to a call center. All of our staff is well-trained and have had years of experience in water treatment.
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Save Money

In the long run, a reverse osmosis system is considerably cheaper than exclusively buying bottled water. The average American Household spends $100 per person a year on bottled water. When storage, transportation, and refrigeration costs are factored, it becomes apparent that an under sink filtration system system is an investment that pays itself out throughout its life cycle.
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Best Taste

The RO-400 guarantees you an optimal level of under sink filtration for it’s price point. With five stages of purification, the RO-400 implements a second “activated carbon” to extinguish an trace of taste in your water.

Lifetime Warranty

Included on Parts & Installation.
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10% Discount

For new customers, Limited time only.
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Top Quality

Modern Technology

What do people think about us on Yelp

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Bought a water softener system a week ago. Their systems are really powerful and efficient,. All the other companies I spoke to seemed to not be sure on my exact water requirements but wanted to push for an installation anyway.

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I haven’t actually purchased anything from Praz. I’m writing this to give a review on how knowledgeable Praz’s manager was regarding water purification. I’m a prospective customer and he spent almost 30 minutes talking to me on the phone to teach me about mineral reduction in RO filters, pH enrichment in alkaline filters, etc. Once I’ve completed my research on what I want to purchase, I am for sure going to Praz because of his knowledge, patience, and friendliness.

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We’ve been with this company for many years and have always had great service and great tasting water. They do tend to call at random times of the evening to remind you about changing your water filter but they always show up on time and do their thing. I never understood how people could live without a water system.

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Discover Why Over 10.000 Customers Choose Praz

Let Us Help to Find The Water Solutions You Deserve.
Commercial Water Filtration in a CUP