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5-Stage Reverse Osmosis System by Tier1

$181.03 List Price $258.99 Save 30%
Availability: In Stock - Free Shipping
  • Ships fast!
  • Less expensive per glass than bottled water
  • System includes all installation parts, filters, housings, and instructions
  • Filters require changing every 6 months; RO membrane every 2-3 years
› See more product details
  • Ships fast!
  • Less expensive per glass than bottled water
  • System includes all installation parts, filters, housings, and instructions
  • Filters require changing every 6 months; RO membrane every 2-3 years
The 5-Stage Reverse Osmosis System by Tier1 is the complete package, using 5 stages to deliver up to 50 gallons of filtered water per day, the Tier1 RO5 is an ideal solution to your drinking water needs. Water travels through Sediment and Activated Carbon pre-filter stages, preventing large particles and chlorine from ever making it to the valuable main filter. This treated water then meets the RO membrane, where dissolved metals, minerals, and salts are separated and rejected straight down a separate waste water drain. This portion of the process captures the nastier contaminants like barium, cadmium, chromium (III and VI), copper, fluoride, lead, mercury, nitrates, nitrites, radium, selenium, and total dissolved solids (TDS). Lastly, the water is polished by a carbon post-filter removing odors, bad tastes, and other hindrances to the perfect drinking/cooking water experience. Once processed, the water is transferred to an automatic shutoff valve equipped storage tank where it waits for you to turn on the tap! This system includes all of necessary parts: starting filters, membranes, housings, brackets, shut-off valve, saddle valves, tubing, fittings, standard long reach chrome faucet, and installation instructions. Order today!

Why use Reverse Osmosis?

Reverse Osmosis is a water purification technology that utilizes a semi-permeable membrane to remove up to 99% of the contaminants from your drinking water. Unlike some traditional water filters, reverse osmosis water filters are able to remove dissolved solids. These are typically referred to as Total Dissolved Solids in water industry testing and measurements.

The dissolution of organic or inorganic matter in water occurs based on water's universal solvency. This means that over time substances, with the exception of oil based materials, will dissolve and become part of the chemical makeup of the water source they reside in. Many of these items are not harmful and Municipal Water Sources are treated to reduce or remove any contaminants harmful to a resident population.

Much like a standard under-sink filter, the critical difference is the semi-permeable membrane that traps specific types of contaminants that standard sediment or carbon filters cannot. For Example, they are the only water filter system certified to remove arsenic, 98% of chlorine and in some cases, Flouride. If you are concerned about the removal of any TDS substance, or a particular chemical or compound in your water, Reverse Osmosis is most likely the best filtration option for you.

What is Reverse Osmosis?

The process of Reverse Osmosis is based on a pressurized or "reversed" form of Osmosis. Water is forced through a semipermeable membrane creating purified water by filtering unwanted particulates and contaminants. Like normal mechanical filtration, the pores of a reverse osmosis membrane only allow the free flow of water molecules, creating a flow to dispense water contaminants through a rejection or "brine" stream. The rejected water is funneled into a holding tank or faucet to be discarded.

Typical Osmosis is based on water flow through a membrane in the pursuit of pressure equalization or normalization. Once such equalization is found, the water flow will cease, stopping any flow between the membrane. When enough pressure is applied to one side so that water flow is stopped completely, Osmotic Equilibrium is attained.

When pressure is added to dictate the flow of the water, this process is changed or "reversed". The process has been titled Reverse Osmosis and provides the basis for all Reverse Osmosis filtration technology. By dictating the flow of the water, the system is able to provide clean water as a result and will flush any contaminants to a drain line for removal or drainage.

What do the filters do?

Reverse Osmosis systems use between 3 and five stages. Although specific designs vary, there are three main types of filters involved in all Reverse Osmosis systems. For your reference, we have included a short description of each of their functions below:

Sediment filters are used to remove physical particulates from a water source. These contaminants include Sand, Rust, Silt, Soil and the like. These are caught in a mesh, screen or wrap that is designed to allow only material of a certain size through it.

The spaces that allow water to flow through them use a measurement called a "Micron" in order to communicate what will and will not be stopped by the filtration media. For your reference, most grains of milled household flower are each 25 microns. Industry Standard Sediment Filters can differ in Micron Size from 0.5 Micron to 100 Microns.

These are designed to catch specific particulates varying from the size of a grain of sand to the size of a micro-organism. Contaminants removed by certain micron ratings are larger than the given channels are caught in the media itself. Correspondingly, larger micron ratings, 50-100 microns, will have an increased flow rate while lesser micron ratings, 1 - 50 Microns, will have a more restricted flow rate.

Primarily, sediment filters used in reverse osmosis systems are Industry Standard 10" by 2.5" filters. This can vary based on the system itself.

Sediment filters are primarily made of one of two different media types: Cellulose or Polypropylene.

Cellulose: Cellulose users prefer this organic plant matter media as it is able to provide excellent small micron and industry-standard filtration. In order to use Cellulose filters however, users must be filtering treated or municipal water. This is because cellulose's organic media makes it susceptible to micro-organism consumption. Some Micro-organisms can feed on the cellulose and this can cause degradation of both the filter and its functionality. There is no fear of this if the cellulose filter is used with treated water so an understanding of the treatment status of your water source is necessary for its use. For more information on cellulose filters, please visit our Resource Center entry here.

Polypropylene: Polypropylene is a plastic-based synthetic media that functions in the same way as cellulose, but does not pose any risk from micro-organisms. It can be made to suit the same micron ranges. However, Polypropylene is a less cost-effective option.

Sediment filters should be chosen based on the largest micron rating possible to filter out the most specific particulates present in your water source. By keeping your micron rating as large as possible, while still being effective, you will provide the needed filtration at the best available flow rate.

Carbon Filters are primarily used to address the "aesthetic" concerns in a water source. In most cases, this is Chlorine Taste and Odor that is created by typical civic water treatments. The water industry considers this function water "polishing". Additional polishing can be applied to water that contains sulfates and other odor-causing contaminants.

Depending on the product itself, Carbon is also capable of removing organic chemicals, herbicides volatile organic compounds and industrial pesticides. In some cases, chlorine and chloramines can also be reduced rather than just having their odor and taste removed.

Carbon Filtration is effective based on its ability to capture contaminants through a process called "Absorption". Pollutant molecules are trapped in the minute pore structure of the carbon media itself. Much like sediment filtration, the particles and unwanted chemicals are trapped in the media while the water is allowed to flow unimpeded through the filter.

Also like Sediment Filters, Carbon Filters are also assigned a Micron rating. This communicates how effective they will be at stopping particulate contaminants. Carbon media is a more expensive material and correspondingly, industry-standard water filtration systems use a Sediment filter previous to a carbon filter. This is done in order to increase the filter life of the Carbon Filter.

By using the sediment filter to capture the majority of the particulates present in the water source, multi-stage systems will allow the carbon filter to utilize its functionality on chemical and polishing filtration. This increases both the benefits of the filtration as well as the cost-effectiveness of the water filtration system.

Reverse Osmosis Membranes primarily use TFM, or Thin Film Membranes. The material is synthetic and can be produced with a porosity of 1/10,000th of a Micron. The filtration provided by such an infinitesimal size restriction is why people are drawn to Reverse Osmosis systems.

To recap some of what has been written previously on this page, similar to a standard mechanical filter, the semi-permeable Reverse Osmosis Membrane traps specific types of contaminants that standard sediment or carbon filters cannot. For Example, they are the only water filter system certified to remove arsenic, 98% of chlorine and in some cases, even Flouride. If you are concerned about the removal of any TDS, or Total Dissolved Solid, or a particular chemical or compound in your water, Reverse Osmosis is most likely the best filtration option for you.

Again, these systems are designed to remove up to 98% of the contaminants found in a given water source. Each system will have its own specifications and testing results based on the quality and design of the membrane as well as the additional parts of the system. Results will also vary based on the quality of the source water being filtered. Reverse Osmosis Membranes may be the final filter in three or four-stage systems or the fourth step in five-stage systems. Regardless of their placement, their function will be the same.

Reverse Osmosis Membranes will have a gallon per day rating that will provide consumers with an understanding of how many gallons of water a membrane can produce for consumption each day. This water is usually stored in a holding tank for later use.

The RO5's Five Stages of Filtration: What do they do?

The 1st stage in any RO system will be a sediment filter designed to remove particular contaminants. These filters should be changed every 3-6 months depending on your water quality. This should be done to ensure a consistent flow rate and preserve the life of the other filters.

The 2nd stage in any RO system will be a carbon filter designed for aesthetic polishing and chemical removal. The RO5 uses a Tier1 carbon block water filter. This filter will make your water taste and smell better. It also reduces chlorine and other such chemical contaminants.

The 3rd stage in the RO5 and any other 5 stage RO is an additional sediment filter. The RO5 uses a Tier1 sediment filter. This additional stage is designed to further reduce the aforementioned contaminants, and extend the life of your filters and system.

The 4th stage in the RO5 system is the RO membrane. The RO5 uses a Tier1 brand RO membrane. During this stage, Reverse Osmosis filtration takes place. This step removes nearly all Total Dissolved Solids from the water including micro-particulates and chemicals.

The 5th stage is an inline carbon filter designed to polish the water coming from the tank. This ensures you have a pleasant taste for water dispensed at a designated RO Faucet. The RO5 uses a Tier1 inline coconut granular activated carbon water filter.

Quality Control and Product Excellence

1. Component Integrity

Our Products begin their lifecyle with a rigorous component integrity examination.

2. Construction Process

After all components pass a full battery of tests, products are carefully assembled and constructed.

3. Testing Process

Each product is put through extensive tests to ensure the best possible performance and quality.

4. Packaging and Shipping

Once our Products have passed inspection, they are cautiously packaged and shipped to ensure they are safe throughout their travels.

5. Final Inspection

Before any products are cleared for shipping, they undergo an additional final inspection to ensure a defect free shipment.

Questions, Concerns and Detractors:

Thus far, we have seen all of the great benefits of using a Reverse Osmosis system. There are a few considerations and questions that many consumers have raised over the years. Included below are the two main questions that concern the use of RO Systems. We have also included an overview of the pertinent information to be aware of when discussing these subjects.

1. If RO systems discard the "Brine" water and contaminants, does that mean it wastes water?

RO Systems are designed to self clean and flush away impurities during its Osmotic process. This will drain a portion of the water. That does mean that there is a material amount of water discarded during this process. However, this is not a constant process. Once your faucet is shut off, or your tank is full, no additional water will be discarded. Water will only be drained from the process while the RO system itself is producing clean water to either feed a faucet, or store in its holding tank. Depending on your water usage, this could increase your daily water usage by up to 9 gallons a day for very active users.

2. If RO systems remove minerals, and mineral consumption is essential to health, does that mean I am reducing my mineral intake? If so, will there be negative side effects?

This is a complicated question but simply put, yes, RO systems remove minerals. However, there will not be any negative side effects. This is because the minerals found in water are not easily digestible. The minerals usually found in water are inorganic and are very difficult for one's body to process. The minerals found in food are primarily organic and much easier to consume. This means that the minerals removed by RO filtration are not a true source of nutrients for the drinker. That portion of our required nutrition should come from our food. RO water is clean and pure and will aid in hydration, which is water's primary purpose in the human diet.

Experience the Tier1 Difference

Tier1 manufactures high-quality filtration and household products. We take creating and maintaining a healthy home seriously. Products must undergo rigorous testing and meet demanding quality expectations in order to earn the Tier1 badge. Every purchase is backed by the Tier1® Guarantee:

  • Guaranteed Fit
  • Guaranteed Quality
  • Guaranteed Price
Package Qty1
Used In BrandsTier1
Manufacturer's IdRO5
Actual Size (in)18 inches (Length) x 14 inches (Width) x 6 inches (Depth)
Operating Pressure (psi)40 - 75
Operating Temperature (°F)40 - 100
Flow Rate (gpm)0.5
Flow Rate (gpd)50
Tank Dimensions15 inches (Length) x 11 inches (Outside Diameter)
Warranty GuaranteeUnconditional Product Guarantee for Life of the Product
IncludesTwo Sediment Filters (5 micron and 1 micron), Two Carbon Filters ( 5 micron Carbon Block and Inline), Reverse Osmosis Membrane, Tank, Component Parts, Chrome Faucet, and Housing Wrench
Primary Filter MediaSemi-Permeable Membrane

Reduced Contaminants

The TIER1-RO5 reduces the following contaminants:

  • Arsenic
  • Barium
  • Cadmium
  • Chlorine Taste & Odor
  • Chromium (III / Trivalent)
  • Chromium (VI / Hexavalent)
  • Copper
  • Cryptosporidium
  • Cysts
  • Fluoride
  • Giardia
  • Lead
  • Mercury
  • Nitrates / Nitrites
  • Radium
  • Selenium
  • Total Dissolved Solids (TDS)
  • Toxoplasmacysts
  • Turbidity

The TIER1-RO5 is comparable with the following part numbers


The TIER1-RO5 fits the following model numbers


Installation Guide

User Guide


  1. For more information see the provided Tier1 5-Stage Reverse Osmosis System Manual
  2. In addition to our manual, we have also provided a step-by-step installation video for your reference below:

  3. When it is time to change your filters, use your filter wrench to unscrew the filter housings. DO NOT use the wrench to tighten the housing sumps because you can damage the o-rings. Please review the below video for a step-by-step guide to changing the filters of your Tier1 RO5: