"Does RO remove even the beneficial minerals?"

"Yes. RO doesn't discriminate — it removes dissolved contaminants and beneficial minerals alike. We can install a final remineralizing stage that adds back calcium and magnesium after the membrane, or you can remineralize manually with trace mineral drops. Either approach gives you purified water with the mineral content you want."

"How much water does an RO system waste?"

"Modern high-efficiency RO systems produce roughly 1:1 — one gallon of purified water per gallon sent to the drain. Older or budget systems can run 3:1 to 5:1. The reject water carries concentrated contaminants out to the drain line. It can't be recaptured, but a high-efficiency system minimizes the loss."

"How does RO water taste?"

"Most customers notice an immediate difference. The mineral heaviness, chlorine aftertaste, and sulfate bitterness that characterize East Valley tap water are gone. Coffee, tea, and cooking water taste noticeably cleaner."

"Can I connect the RO system to my refrigerator?"

"Yes. We can plumb a dedicated line from the RO system to the ice maker and water dispenser during installation, or return for an add-on visit if you decide to add it later. Many newer homes are already pre-plumbed with a line from under the sink to the fridge. One note: do not run RO water through your refrigerator's built-in filter — some fridges operate without it, others require a bypass cap (several manufacturers will ship one free of charge)."

"Do I need RO if I already have a water softener or whole-home filtration system?"

"They serve different purposes. A softener handles hardness and scale — it protects your pipes, appliances, shower glass, laundry, and dishes, and it does that job well. RO handles what a softener can't: arsenic, PFAS, nitrate, and TDS at the drinking tap. For East Valley water quality, both are the right call."

"Does RO remove even the beneficial minerals?"

"Yes. RO doesn't discriminate — it removes dissolved contaminants and beneficial minerals alike. We can install a final remineralizing stage that adds back calcium and magnesium after the membrane, or you can remineralize manually with trace mineral drops. Either approach gives you purified water with the mineral content you want."

"How much water does an RO system waste?"

"Modern high-efficiency RO systems produce roughly 1:1 — one gallon of purified water per gallon sent to the drain. Older or budget systems can run 3:1 to 5:1. The reject water carries concentrated contaminants out to the drain line. It can't be recaptured, but a high-efficiency system minimizes the loss."

"How does RO water taste?"

"Most customers notice an immediate difference. The mineral heaviness, chlorine aftertaste, and sulfate bitterness that characterize East Valley tap water are gone. Coffee, tea, and cooking water taste noticeably cleaner."

"Can I connect the RO system to my refrigerator?"

"Yes. We can plumb a dedicated line from the RO system to the ice maker and water dispenser during installation, or return for an add-on visit if you decide to add it later. Many newer homes are already pre-plumbed with a line from under the sink to the fridge. One note: do not run RO water through your refrigerator's built-in filter — some fridges operate without it, others require a bypass cap (several manufacturers will ship one free of charge)."

"Do I need RO if I already have a water softener or whole-home filtration system?"

"They serve different purposes. A softener handles hardness and scale — it protects your pipes, appliances, shower glass, laundry, and dishes, and it does that job well. RO handles what a softener can't: arsenic, PFAS, nitrate, and TDS at the drinking tap. For East Valley water quality, both are the right call."

Reverse Osmosis Installation — East Valley, AZ

Your Water Has Contaminates That Pitcher Filters CANNOT remove

Gilbert’s arsenic reaches the federal legal limit. Tempe’s PFOS is 750% of the 2029 federal MCL. San Tan Valley’s nitrate sits at 93% of the maximum contaminant level. No water softener, sediment filter, carbon filter, or salt-free conditioner removes any of these. Only one residential water treatment technology reliably addresses all three: reverse osmosis.

Contaminant	Removal Rate	Why It Matters in the East Valley
Arsenic	95%+	Gilbert reaches the MCL (10.5 ppb); Chandler at 86% of MCL; no safe exposure level
PFAS / forever chemicals	90%+	Tempe PFOS at 30 ppt — 750% of the 2029 federal limit; PFAS detected in every East Valley city
Nitrate	85–95%	San Tan Valley at 9.34 ppm (93% of MCL); particular concern for infants and pregnant women
TDS (total dissolved solids)	90–99% reduction	Gilbert avg 795 ppm; Mesa peaks at 970 ppm; EPA secondary standard is 500 ppm
Lead and heavy metals	95%+	Aging service lines; no safe level for lead; chromium-6 and barium also addressed
Chlorine and chloramines	Yes (carbon stage)	Taste, odor, and disinfection byproduct precursors throughout the service area
VOCs and disinfection byproducts	Yes (carbon stage)	Chandler TTHMs at 81% of MCL; VOCs from agricultural and industrial activity
Hardness (at the drinking tap)	Yes	Eliminates scale in kettles, coffee makers, and ice machines

How Reverse Osmosis Works

A reverse osmosis membrane has pores small enough to exclude virtually anything that isn’t water — approximately 0.0001–0.001 microns. Water is forced through the membrane under household pressure, and dissolved minerals, metals, and chemicals — arsenic, PFAS, nitrate, lead, chlorine, and dissolved solids — stay behind and are flushed to the drain.

A residential RO system is a staged process, not just the membrane:

Sediment pre-filter — removes particles, rust, and sediment that would wear down the membrane
Carbon pre-filter(s) — removes chlorine and chloramines, which degrade the membrane over time
RO membrane — the core filtration stage; rejects 90–99% of dissolved contaminants
Pressurized storage tank — holds filtered water so it’s ready on demand
Carbon post-filter (polishing stage) — a final pass to polish stored water before it reaches your faucet

What Reverse Osmosis Removes

A note on arsenic and chlorination: Some argue that RO is less effective against arsenic III (trivalent arsenic). This is technically true in unchlorinated water. Because East Valley municipal water is chlorinated, a significant portion of arsenic III is oxidized to arsenic V — which RO removes at 95%+. This is not a meaningful limitation for city water customers in our service area.

Under-Sink RO and Whole-Home Filtration

These aren’t competing options — they solve different problems and work best together.

Whole-home filtration (sediment, carbon, and softener stages) treats every gallon that enters the house. These systems do important work, but none of them touch arsenic, PFAS, or nitrate. Not even partially. If you have an existing system and want confirmation, we’ll test your water.

Under-sink RO picks up where whole-home filtration stops. It installs in the cabinet under the kitchen sink, delivers purified water through a dedicated faucet, and reduces TDS by 90–99%, removes arsenic at 95%+, and eliminates PFAS and nitrate. It treats the water you drink and cook with — the water that actually enters your body.

A whole-home filtration system is not a substitute for RO. The contaminants that make East Valley water genuinely concerning — arsenic near the legal limit, PFAS well above upcoming federal limits, nitrate approaching the MCL — require a membrane. Chlorine removal and scale prevention are valuable, but they don’t get you there.

The right setup for most East Valley homes is both: whole-home filtration for plumbing and appliances, under-sink RO for drinking and cooking water. See Whole Home Filtration for how the treatment stages stack together, and Water Softeners for detail on hardness and scale protection.

Filter Maintenance Schedule

An RO system lasts for years with routine filter changes. Skipping maintenance — particularly on the pre-filters — shortens membrane life and degrades water quality.

Stage	Replacement Interval
Sediment pre-filter	Every 6–12 months
Carbon pre-filter(s)	Every 6–12 months
RO membrane	Every 2–3 years
Carbon post-filter	Every 12 months

Reverse Osmosis Installation

Under-Sink RO Installation for East Valley Homes

Your Water Has Contaminates That Pitcher Filters CANNOT remove

How Reverse Osmosis Works

What Reverse Osmosis Removes

Under-Sink RO and Whole-Home Filtration

Filter Maintenance Schedule

Frequently Asked Questions

Get an RO System Quote

Serving the Phoenix East Valley

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