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5-stage reverse osmosis system with storage tank.
A proven under-sink reverse osmosis system with five stages, including an alkaline stage, and a small pressurized storage tank. It makes up to 100 gallons per day and delivers purified water through a dedicated faucet.
5-Stage Tank Reverse Osmosis: quick answers
Tank or tankless?
Tankless saves space and wastes less water; a tank system is a simple, proven alternative.
Compare it with our tankless RO.
How much does it make?
Up to 100 gallons per day, stored in a tank under the sink.
That’s plenty for drinking and cooking in most homes.
Does it include remineralization?
Yes. One of the five stages is an alkaline stage that adds minerals back for taste.
5-Stage Tank RO specifications
| Production | Up to 100 gallons per day |
|---|---|
| Stages | 5, including an alkaline stage |
| Storage | Pressurized storage tank under the sink |
| Faucet | Dedicated faucet in brushed nickel, chrome, brushed gold, matte black or oil-rubbed bronze |
Specifications from the distributor’s product sheet.
Who it’s for
- Homes that prefer a traditional tank system
- Kitchens with room under the sink
What it won’t do
- It treats one faucet, not the whole house.
- The tank takes cabinet space.
- Filters need scheduled replacement.
What reverse osmosis reduces
The CDC lists reverse osmosis as effective at removing common chemical contaminants such as sodium, chloride, copper, chromium and lead, and says it may reduce arsenic, fluoride, radium, sulfate, calcium, magnesium, potassium, nitrate and phosphorus (CDC: home water treatment). Results depend on your water and on filter upkeep, so we test before and after installation.
Warranty
| Reverse osmosis system | 1 year |
|---|---|
| Installation labor | 1 year from purchase |
Coverage applies to the original purchaser under normal operating conditions. Read the full warranty →
Price
Most Happy Tap systems fall between $2,950 and $6,950, depending on the setup: city or well water, the size of your home and household, and how much plumbing the install needs. Your quote is one written number before any work starts. Installation is available through licensed Arizona plumbing professionals.
Frequently asked questions
How often are filters changed?
Generally about once a year, depending on use. Care Plan members get RO filter replacements included.
Is a tank system worse than tankless?
Not worse, just different. Tankless saves space and water; a tank system stores water for fast filling.
Other Happy Tap systems
Standard Softener + Filtration
48,000 grains. Softening and chlorine filtration in one tank. Our most popular system.
View system →XL Softener + Filtration
64,000 grains for larger homes, bigger households or harder water.
View system →Dual Tank: City Water
96,000 grains with a separate carbon tank that backwashes itself.
View system →Dual Tank: Well Water
Softening plus Katalox Light media for iron, manganese and sulfur smell.
View system →Salt-Free Conditioner
Scale prevention with no salt, no drain and no power. Does not soften.
View system →Tankless RO (800 GPD)
Seven stages, water on demand, no storage tank under the sink.
View system →Add-ons: Alkaline & UV
Remineralize RO water, or add whole-home UV for well water.
View system →Not sure which one fits?
We test your water at your sink, explain the numbers, and size the system to your home. Free, and no pressure.