RO, Ultrafiltration & Whole-Home Filtration
We work with two core technologies — reverse osmosis and ultrafiltration — and we know them well. Most situations call for one or the other, sometimes both. Here's how each works and what it's good for.
Not sure which one applies to you? That's what the free water test is for.
Reverse Osmosis Systems (RO)
RO is the most thorough filtration technology available for home use. Water gets pushed through a membrane with pores so small that dissolved salts, heavy metals, and most contaminants can't pass through.
A typical under-sink RO system has four or five stages — sediment pre-filter, carbon block, the RO membrane itself, and a post-carbon polishing filter. Some include a remineralization stage that adds a small amount of calcium and magnesium back in for taste. Most systems connect directly to a dedicated tap on your sink and include a small storage tank so you always have filtered water ready.
What it removes
- Chlorine and chloramine
- Fluoride
- Lead and heavy metals
- Nitrates and nitrites
- TDS (total dissolved solids)
- Arsenic
- Pharmaceuticals and PFAS
- Most bacteria and viruses
Worth knowing
- Wastes some water in the filtration process (typically 3:1 ratio, though newer systems are better)
- Removes minerals — some people add a remineralizer stage
- Produces water at a slower flow rate, stored in a tank under the sink
- Filters typically need replacing every 6–12 months depending on use
Best for
- Households with high TDS or hard water
- Anyone concerned about lead, fluoride, or PFAS
- Homes on municipal water with taste or odor issues
- Families who buy a lot of bottled water
Ultrafiltration Systems (UF)
UF uses hollow fiber membranes to physically filter out particles, bacteria, and viruses while leaving dissolved minerals in the water. Think of it as a very fine physical strainer rather than a chemical separation process.
Because UF doesn't strip out dissolved minerals the way RO does, many people find the water tastes more natural. It's also more efficient — there's very little waste water, and the flow rate is much higher than RO, making it practical for whole-home installation. A point-of-entry UF system treats all the water entering your house, so you get filtered water from every tap, shower, and appliance.
What it removes
- Bacteria and viruses
- Sediment and turbidity
- Cysts (Giardia, Cryptosporidium)
- Chlorine (with carbon pre-filter)
- Rust and particulates
- Some heavy metals (with additional media)
Worth knowing
- Does not remove dissolved salts or TDS the way RO does
- For high TDS or hard water, RO is usually the better choice
- Membranes need periodic backwashing or replacement (usually annually)
- Excellent option for well water with biological contamination concerns
Best for
- Whole-home filtration where RO flow rate would be limiting
- Well water with bacteria or turbidity issues
- People who want filtered water at every tap
- Those who prefer to keep naturally occurring minerals in their water
Whole-Home Filtration (Whole Home)
A whole-home system installs at the point where water enters your house — meaning everything downstream gets treated. Every tap, every shower, the washing machine, the refrigerator. Not just the kitchen faucet.
We typically build whole-home setups around a UF membrane with a sediment pre-filter and carbon stage for chlorine removal. In some cases we combine a whole-home system with an under-sink RO unit for drinking and cooking water, which gives you the best of both — clean water throughout the house plus the highest-purity water at the kitchen tap. The right configuration depends on your water quality and what you're trying to achieve.
What it removes
- Sediment, rust, and particulates
- Chlorine and chloramine (carbon stage)
- Bacteria and viruses (UF membrane)
- Turbidity and color
- Some heavy metals depending on media
Worth knowing
- Requires professional installation at the main water line
- System sizing matters — needs to match your home's peak flow demand
- Some systems require a backwash drain line
- Annual filter and membrane service keeps it running properly
Best for
- Households that want filtered water throughout, not just at one tap
- Homes with skin or hair sensitivity to chlorinated water
- Well water households
- Anyone combining whole-home with an under-sink RO for drinking water
Under-Sink & Countertop Systems (Under-Sink)
If you mainly want better drinking and cooking water — and don't need to filter the whole house — an under-sink system is often the most practical answer. It sits out of sight under your kitchen sink and feeds a dedicated tap.
Most of the RO systems we install are under-sink units. They're compact, relatively simple to maintain, and produce noticeably better water. We also install under-sink UF systems for customers who want high-flow filtered drinking water without the permeate tank that RO requires. Countertop options exist too, though we generally find the under-sink installation is cleaner and more practical for long-term use.
What it removes
- Depends on configuration (RO or UF)
- Carbon stages for chlorine and taste
- Sediment pre-filtration
- Full contaminant removal with RO membrane
Worth knowing
- Only filters water at that specific tap
- Easy to maintain — filter changes every 6–12 months
- RO version requires a storage tank and dedicated tap
- UF version has faster flow, no storage tank needed
Best for
- Apartments and rentals where a whole-home system isn't practical
- Homeowners who mainly want better drinking and cooking water
- Anyone upgrading from a pitcher filter or bottled water
- Most straightforward and cost-effective entry point
RO vs. UF — the short version
Both are excellent technologies. The right one depends on your water quality and what problem you're trying to solve.
| Reverse Osmosis | Ultrafiltration | |
|---|---|---|
| Removes dissolved salts / TDS | Yes | No |
| Removes bacteria and viruses | Yes | Yes |
| Keeps minerals in water | No (can add back) | Yes |
| Flow rate | Slower (uses storage tank) | Fast (no tank needed) |
| Waste water | Some (improving in newer systems) | Very little |
| Best installation point | Under-sink (point of use) | Whole home or under-sink |
| Ideal for high TDS / hard water | Yes | Not ideal |
Many homes benefit from a whole-home UF system plus an under-sink RO for drinking and cooking water.
Let the water test decide for you.
Once we know what's actually in your water, the right system becomes pretty obvious. The test is free and there's no obligation.