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Servicing Maricopa and Pinal Counties

Whole Home Filtration

Whole Home Water Filtration for the East Valley

Your water is hard, chlorinated, and contaminated with agricultural runoff. Here’s the data. Thanks to regulations, each of our cities performs up to 100 water tests per day from public and private taps all around town. We use this data to design and recommend a system that aligns with your water treatment goals.

What does all of this data mean? Let’s get into it below. We’d love to help you make an informed decision.

City Hardness (gpg) TDS (ppm) Arsenic (ppb) Nitrate (ppm) Chlorine (ppm) Standout Issue
Gilbert 6.3–20.7 (avg 13) 441–942 (avg 795) ND–10.5 (hits MCL) ND–7.01 0.20–1.89 PFAS detected; highest avg TDS in service area
Chandler 10.1–16.8 Not reported in CCR, indepedent labs report 600-700 8.6 (86% of MCL) 6.2 0.05–2.16 PFAS detected; TTHMs at 81% of MCL
Mesa 0.5–25 190–970 8.37 (84% of MCL) 7.88 (79% of MCL) 0.01–1.82 Widest hardness range; TDS peaks at 970
Scottsdale 13–17 325–710 8.4 (84% of MCL) 0.2–4.9 0–1.5 Uranium at 47% of MCL (no safe level); high sulfate causes bitter taste
Tempe 9.9–33 (avg 11.3) Not reported in CCR, independent labs report 600-700 up to 5 ND–7 (70% of MCL) 0.02–1.1 PFOS at 30 ppt — 750% of 2029 MCL
Phoenix 9.2–20.1 560–686 ND–8.3 ND–8.2 0.17–1.95 TDS exceeds EPA secondary standard; seasonal algae taste
Queen Creek ~6.4–15.2 (avg 12) 351–652 (avg 500) up to 4.8 6.88 (69% of MCL) 0.30–1.69 Lithium at 152 ppb (unregulated)
San Tan Valley 15–18 Not reported in CCR, independent labs report 700-800+ 5.2 9.34 (93% of MCL) 1.3 Nitrate nearly at legal limit
Paradise Valley 12 430–490 7.71 (77% of MCL) 4.8 0.77–1.02 Supplied partly by Phoenix plant

You can click your city to view the official consumer confidence report and lab results.

Question: What about whats coming out of MY tap? Contamination (such as agricultural runoff) and treatment (such as adding chlorine) happens at the source, not in the pipes between the source and your tap. What’s more: cities mix in different sources of water throughout the year, like the Colorado River, Salt and Verde rivers, and groundwater. We can absolutely perform an in-home test at your tap, and for some homes that’s the right decision. But an in-home test will yield results within the city’s provided range, leading to the same configuration recommendation. In fact, a clients needs and goals influence the design of the system more than for example, wether the arsenic level is 5 or 8 ppb – we’ll be targeting arsenic with the same effective method in either case.

Which Filter Addresses Which Contaminant

Filter Type Hardness / Scale TDS Arsenic Nitrate PFAS VOCs / DBPs Chlorine / Taste Sediment
Sediment Filter Yes
Carbon Filter Partial (carbon block) Yes Yes Partial (block only)
Salt Softener Removes completely
TAC Conditioner (salt-free) Prevents scale adhesion only†
Under-Sink RO Removes (at drinking tap) 90–99% reduction 95%+ 85–95% 90%+ Yes (with carbon stage) Yes (with carbon stage) Yes (with pre-filter)
UV Disinfection

†TAC does not remove hardness minerals — water remains chemically hard. Effectiveness decreases significantly above ~18 gpg; less reliable for East Valley peak hardness levels (Mesa 25 gpg, Tempe groundwater 33 gpg).

UV is not shown for the contaminants above because it addresses bacteria and pathogens only — not dissolved minerals or chemicals. Relevant for well water users and as a post-RO add-on.


What Each Treatment Method Actually Does

Water treatment companies market their products with dramatic promises. Here’s a straightforward breakdown of what each technology does — and just as importantly, what it doesn’t.

Sediment Filtration

A sediment filter is a mechanical barrier, rated in microns, that removes particles: sand, rust, silt, and debris from aging pipes. It doesn’t interact with anything dissolved in the water. Its primary job is protecting downstream equipment — softeners, carbon filters, and RO membranes all wear out faster without it.

Addresses: Particulate, rust, sediment
Does not address: Hardness, arsenic, PFAS, nitrate, chlorine, TDS

Activated Carbon Filtration

Carbon has an enormous surface area at the molecular level. Water passing through a carbon filter leaves behind chlorine, chloramines, VOCs, and some disinfection byproducts — including TTHMs, which Chandler reports at 81% of the legal limit. It significantly improves taste and odor.

Granular activated carbon (GAC) and carbon block are the two common forms. Carbon block is denser and more effective at trapping PFAS, which is particularly relevant for Tempe, Gilbert, and Chandler customers.

Addresses: Chlorine, chloramines, taste and odor, VOCs, some PFAS (carbon block / NSF-certified GAC), some TTHMs
Does not address: Hardness, arsenic, nitrate, TDS

Salt-Based Water Softener

Ion exchange is the only process that actually removes hardness minerals from water. The softener’s resin tank holds sodium ions; calcium and magnesium in the incoming water displace those ions and stay trapped in the resin. The result is water with no measurable hardness — and no more scale buildup on fixtures, in pipes, or inside water heaters.

Given East Valley hardness levels (Gilbert averages 13 gpg, Mesa peaks at 25 gpg, Tempe groundwater at 33 gpg), a salt-based softener is the most reliable solution for scale prevention, appliance protection, and everyday water quality.

Addresses: Hardness and scale (completely), appliance and pipe protection, soap lathering, skin and hair feel
Does not address: Arsenic, PFAS, nitrate, TDS (softeners exchange ions — they don’t reduce total dissolved solids), chlorine or taste

Note on sodium: The sodium added by a softener is minimal and not a health concern for most people. If someone in the home is on a medically sodium-restricted diet, an under-sink RO on the drinking water line solves this cleanly — RO removes the sodium along with everything else.

TAC Conditioner (Salt-Free “Softener”)

TAC (Template Assisted Crystallization) is a physical process, not a chemical one. It converts dissolved calcium carbonate into microscopic crystals that stay suspended in the water rather than forming sticky scale deposits on surfaces. The hardness minerals are still in the water — they just don’t adhere.

Where this matters: TAC prevents scale adhesion in pipes, water heaters, and appliances — no salt, no regeneration cycles, no wastewater discharge. For customers who strongly prefer to avoid salt, it’s a legitimate option.

Where the limits are:

  • It does not remove hardness minerals. The water remains chemically hard — it won’t improve soap lathering, skin feel, or hair.
  • Its effectiveness degrades significantly above roughly 18–20 gpg. East Valley water regularly exceeds this ceiling — Mesa peaks at 25 gpg, Tempe groundwater blends at 33 gpg.
  • Because municipal hardness varies seasonally as water sources are blended, a system that performs adequately in spring may underperform in summer when hardness spikes.

We offer TAC systems, and we’ll walk you through what they do and don’t address for your specific supply zone. They’re a reasonable fit in certain situations. They’re not a substitute for a salt softener in the most hard-water-affected parts of the service area.

Addresses: Scale adhesion prevention (not hardness removal), some appliance protection in moderate hardness
Does not address: Hardness removal, lathering or skin/hair improvement, arsenic, PFAS, nitrate, TDS, chlorine; substantially less effective above ~18 gpg

Reverse Osmosis (Under-Sink)

A reverse osmosis membrane has pores small enough to exclude virtually anything that isn’t water. Under normal household pressure, water is pushed through the membrane, leaving dissolved minerals, metals, and chemicals behind. Residential RO systems include sediment and carbon pre-filter stages and a polishing post-filter.

RO is the only technology that addresses the contaminants the data above flags as most serious: arsenic (Gilbert reaches the legal limit at 10.5 ppb), PFAS (Tempe’s PFOS is 7.5× the 2029 federal limit), and nitrate (San Tan Valley at 93% of the MCL). No softener, conditioner, or carbon filter handles these. Some people argue that RO is not fully effective at removing arsenic 3. However, because our water is chlorinated, a significant portion of the arsenic 3 is oxidized to arsenic 5, which is effectively removed with RO.

Under-sink RO is point-of-use — it treats drinking and cooking water at the kitchen tap. Paired with whole-home filtration, it covers both bases: softened and dechlorinated water throughout the house and purified drinking water at the tap.

Addresses: Arsenic (95%+), PFAS (90%+), nitrate (85–95%), TDS (90–99% reduction), hardness, chlorine, heavy metals, disinfection byproducts
Does not address: Scale protection for whole-home pipes and fixtures (point-of-use only)

Learn More!

UV Disinfection (Add-On)

Ultraviolet light inactivates bacteria, viruses, and other pathogens without adding chemicals. Municipal East Valley water is already chlorinated, so UV isn’t necessary for standard city water customers. It’s relevant for well water users, households with immunocompromised members, or as a final stage after RO — since RO removes the residual chlorine that would otherwise suppress bacterial regrowth in the storage tank.

Addresses: Bacteria, viruses, pathogens
Does not address: Any dissolved contaminants, hardness, taste, or chemical concerns


Building the Right System

For most East Valley homes, the most effective approach stacks treatments in sequence:

  1. Sediment pre-filter — removes particulate and protects everything downstream
  2. Carbon filter — chlorine, taste, odor, and some PFAS
  3. Salt-based water softener — eliminates hardness throughout the house
  4. Under-sink RO — drinking and cooking water: arsenic, PFAS, nitrate, TDS

This isn’t a pitch for the most expensive possible system, it’s what the water data calls for. A softener alone doesn’t touch arsenic or PFAS. RO alone treats drinking water but leaves your pipes, water heater, and appliances exposed to scale. The layered stack addresses each problem with the right tool.

For customers who prefer to avoid salt: a TAC conditioner can replace the softener with honest expectations about what that means for your hardness level and water source. We’ll tell you whether it makes sense for your zone.

For well water or immunocompromised households: UV disinfection is available as a final stage after filtration.

Whole-home RO with remineralization Drinkable, RO-quality water at every tap is available for customers who want it. It’s a more significant investment and involves remineralizing the output to prevent corrosion from ultra-pure water. Ask us about it.

Frequently Asked Questions

What's the difference between a water softener and a whole-home filtration system?
A water softener is a single treatment stage — it removes hardness minerals through ion exchange. A whole-home filtration system is a stack: sediment pre-filter, carbon filter, softener, and optionally reverse osmosis at the drinking tap. Hardness is one of several problems in East Valley water. Arsenic, PFAS, and nitrate require different technologies that a water softener alone doesn’t address.
Is a salt-free conditioner as effective as a water softener in the East Valley?
For most of our service area, no — and we’ll tell you that upfront. TAC conditioners prevent scale from adhering to surfaces, but the hardness minerals stay in the water. TAC’s effectiveness drops off significantly above roughly 18 gpg. Mesa peaks at 25 gpg, Tempe groundwater blends hit 33 gpg. We install TAC systems for customers who prefer to avoid salt, but we walk through what that means for their specific supply zone first.
If I have under-sink RO, do I still need a water softener?
Yes, for most homes. RO treats one tap — drinking and cooking water, at a few gallons per hour. The rest of your home sees unfiltered municipal water: pipes, water heater, dishwasher, showerheads, and washing machine. Hard water continues scaling all of those regardless of what’s happening under the kitchen sink. A softener protects the whole house. RO and a softener do different jobs; most complete systems include both.
How often does a whole-home filtration system need maintenance?
Sediment pre-filters typically need replacement every 3–6 months depending on sediment load. Carbon filters last roughly 6–12 months. Salt-based softeners need salt topped off every 4–8 weeks and an annual service check. UV bulbs replace annually. We set up a maintenance schedule at installation so you know what’s due and when.
Why aren't we recommending specialized arsenic filtration for the entire home?
Arsenic isn’t readily absorbed through the skin. Well-water homes should certainly test for arsenic and adding a specialized arsenic filtration tank to the whole-home arsenal may be necessary. For the arsenic ranges showing up on lab tests in our East Valley cities, it is unnecessary and costly. The science strongly supports RO at point-of-use for effectively filtering out arsenic from drinking water.
What about whats coming out of MY tap?
Contamination (such as agricultural runoff) and treatment (such as adding chlorine) happens at the source, not in the pipes between the source and your tap. We can absolutely perform an in-home test at your tap, and for some homes that’s the right decision. But an in-home test will yield results within the city’s provided range, leading to the same configuration recommendation. In fact, a clients needs and goals influence the design of the system more than for example, wether the arsenic level is 5 or 8 ppb – we’ll be targeting arsenic with the same effective method in either case.

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