Six stages of reverse osmosis under your kitchen sink. The softener handles the whole house — the Ultra-6 gives you one tap of near-pure water for drinking, cooking, coffee and ice. It is a separate product from the Pro Plus softener and is sold separately.
Five housings, six stages, a storage tank and a dedicated faucet.
The Ultra-6 mounts under the sink and feeds a dedicated drinking water faucet. Water passes through sediment, carbon and KDF/GAC pre-treatment, then through a thin-film composite membrane that rejects dissolved solids, and finally through a post-carbon polish on its way to the tap.
Reverse osmosis forces ordinary tap water through a semi-permeable membrane, leaving unwanted substances behind to be rinsed away. The five stages around the membrane exist to protect it and to make the water taste right on the way out.
A five micron sediment filter traps dirt, silt, rust and other particulate matter — the things that affect how your water looks, and that would otherwise reach the membrane.
A five micron carbon block greatly reduces chlorine and the other materials that cause bad taste and odor.
Kinetic Degradation Fluxion — a high-purity copper-zinc formulation that removes chlorine, lead, mercury, iron and hydrogen sulfide. Taking these out ahead of the membrane is what prolongs its life.
Granular activated carbon, sharing the housing with the KDF. Its very large adsorption surface area removes chlorine taste and odor and reduces VOCs, while its design keeps flow to the membrane high.
The heart of the system: a 50 GPD thin-film composite membrane that removes total dissolved solids, including sodium, along with contaminants such as chromium, arsenic, copper and lead, and cysts including Giardia and Cryptosporidium.
Water leaves the storage tank through a final high-quality carbon filter on its way to the faucet — the polish that decides what the glass actually tastes like.
The Ultra-6 has been tested according to NSF/ANSI 58 for reduction of the substances below. These are the manufacturer's test results, not estimates — average influent, average effluent, and the reduction achieved.
| Substance | Average in (mg/L) | Average out (mg/L) | Reduction |
|---|---|---|---|
| Total dissolved solids | 741 | 22 | 97.0% |
| Lead | 0.15 | 0.002 | 98.8% |
| Arsenic (pentavalent)1 | 0.310 | 0.001 | 99.6% |
| Cysts (Giardia, Cryptosporidium) | 92,000 per mL | 3 per mL | 99.99% |
| Barium | 9.2 | 0.08 | 99.0% |
| Cadmium | 0.031 | 0.0004 | 98.0% |
| Chromium (hexavalent) | 0.30 | 0.002 | 99.0% |
| Chromium (trivalent) | 0.30 | 0.001 | 99.0% |
| Copper | 3.2 | 0.02 | 99.0% |
| Fluoride | 8.7 | 0.19 | 97.0% |
| Selenium | 94.85 | <0.2 | 97.0% |
| Radium 226/228 | 25 pCi/L | 5 pCi/L | 80.0% |
| Turbidity | 11.3 | 0.1 | 99.0% |
Tested at 50 psi, pH 7.24–7.64. Recovery 15.77%, efficiency 8.82%, daily production rate 18.43 GPD under those test conditions. Your results depend on your incoming water, your pressure and your temperature — which is exactly what the free water test is for.
Two things worth knowing before you buy on the arsenic number.
The system is tested for pentavalent arsenic at concentrations of 0.30 mg/L or less. It reduces pentavalent arsenic but may not remove other forms, and it is meant to be used on supplies that carry a detectable free chlorine residual at the inlet or that have been shown to contain only pentavalent arsenic.
That matters locally. The City of Tampa disinfects with chloramine, and treatment with chloramine is not sufficient to convert trivalent arsenic to pentavalent. If arsenic is your specific concern and you're on Tampa water, say so at your water test and we'll test for it rather than assume this unit answers it. On free-chlorine systems like OUC in Orlando, the precondition is met.
What it will not do. Reverse osmosis treats one tap, not the house. It does not soften the water in your shower, your washing machine or your water heater — that's the softener's job, and the two are different purchases solving different problems. RO also sends some water to the drain as part of how it works.
Ion exchange removes the calcium and magnesium that cause scale, soap curd and appliance wear. It changes how your showers feel, how your laundry comes out, and how long your water heater lasts. What it does not do is remove dissolved solids, nitrate, or most trace contaminants — it isn't designed to.
Reverse osmosis pushes water through a semi-permeable membrane that rejects a wide range of dissolved substances, then polishes the result through carbon. It's slow and it produces some waste water, which is why it goes on one faucet rather than the whole house.
They work best together, but they are two purchases. The Ultra-6 is sold separately from the Pro Plus and is not included in the softener's installed price. Softened feed water is easier on an RO membrane — hardness is one of the main things that fouls and shortens membrane life. That's why the two are usually installed on the same visit, and why most of our customers who add RO do it at the same time as the softener rather than later.
On the 50 GPD figure. That is the membrane's rating. Under the NSF/ANSI 58 test conditions — 50 psi, roughly neutral pH — measured daily production was 18.43 gallons. Both numbers are true and they describe different things: the rating is the membrane's capacity, the tested figure is what a standardised test produced. Either way it is far more drinking water than a household uses, which is why the tank exists.
Maintenance. Filters and the membrane are replaceable cartridges. Change intervals depend on your incoming water — sediment and chlorine load are what wear the pre-filters, and hardness is what shortens membrane life, which is the other reason RO and a softener go in together. We set your schedule from your test results rather than from a generic calendar, and we stock the cartridges in Jacksonville.
They solve different problems. The softener stops scale, soap curd and appliance wear across the whole house. RO improves what you drink and cook with by removing dissolved solids and a long list of trace contaminants at one tap. Plenty of homes are happy with just the softener. If your concern is taste, or a specific contaminant in your utility's report, that's the RO conversation.
The Ultra-6 is sold separately from the Pro Plus softener and isn't included in the softener's installed price. We price it at the free water test, once we know what's in your water and what your kitchen looks like under the sink. You get a written price on the spot, and there's no obligation to take it.
Reverse osmosis is generally effective against PFAS, but PFAS is not among the substances this system was tested for under NSF/ANSI 58, so we don't make a certified claim about it. If PFAS is your reason for asking — and in Tampa it reasonably might be — tell us at the water test and we'll talk about what is actually certified for that.
Yes. Reverse osmosis sends some water to the drain as part of how the membrane works; that's true of every RO system. Under the NSF test conditions this one recovers 15.77% of the water fed to it. We'd rather tell you that up front than have you find it on a spec sheet later.
It takes out dissolved solids broadly, which includes calcium and magnesium along with the things you'd rather not drink. If that matters to you, it's worth raising — diet, not drinking water, is where most people get those minerals, but it's a fair question and we won't wave it away.
Usually, yes, depending on the run from under the sink to the appliance. It's a common request. We'll look at it during the in-home visit and tell you whether it's straightforward in your kitchen.
Tell us who you are and when suits you. A local Otter technician calls to confirm, then brings your price in writing — before you spend $THOUSANDS more at the national brands.