Reverse Osmosis for Midland Kitchens and Whole Homes
RO is the step that turns softened water into drinking water with very little left in it. Most Midland homes put it at one faucet; a few treat the whole house.
Under-sink reverse osmosis typically costs $150–$1,300 installed and whole-home RO $1,000–$4,800 (This Old House). RO pushes water through a membrane that rejects most dissolved minerals and salts. In Midland's very hard water it works best after a softener, which protects the membrane from scale.
What RO takes out
A reverse osmosis membrane rejects most dissolved solids: calcium and magnesium, the sodium a softener adds, and many trace minerals. Midland's 2025 report lists arsenic between 1.5 and 9.19 ppb, within the 10 ppb federal limit, and fluoride up to 1.52 ppm, within the 4 ppm limit (City of Midland 2025 CCR). RO reduces both. Some households want that; others would rather keep fluoride, so it's worth deciding before you buy.
Under-sink or whole-home
Under-sink (point of use): pre-filters, a membrane, a small storage tank and a dedicated faucet. It covers drinking and cooking water, fits most kitchens, and can feed a refrigerator line.
Whole-home (point of entry): treats every tap, needs a large storage tank and a pump, and almost always needs a softener ahead of it in water as hard as Midland's. It costs more to buy and run, and it sends more water to the drain.
A permeate pump or a tank with a shut-off valve cuts drain water on under-sink units, which is worth asking about.
Licensing for RO work
TCEQ issues Water Treatment Specialist licenses in three classes, and its Class III description is the one that explicitly covers reverse osmosis and deionization equipment (TCEQ). Licensed plumbers are exempt. Ask which license the installer holds.
What to compare
- Testing to NSF/ANSI Standard 58, and the specific contaminants listed on the performance data sheet.
- The ratio of drain water to filtered water.
- Tank size, and room under the sink.
- Membrane replacement cost: This Old House puts it at $50–$100 every three to five years.
For every system side by side, see installed prices for Midland water treatment.
Questions homeowners ask
Do I need a softener if I have RO?
For drinking water, RO alone is fine. But RO at one faucet does nothing for the shower, the water heater or the dishwasher, and very hard water shortens membrane life. Most Midland homes that add RO also soften.
How much water does RO send to the drain?
It varies by model. Older designs waste several gallons per gallon filtered; newer ones are much more efficient. Compare the ratio on the spec sheet.
Can RO feed my refrigerator's ice maker?
Yes. Most under-sink systems have a fitting for a refrigerator line. Clearer ice with less white residue is one of the first things people notice.
Ask for a free Midland water test
Tell us what you're dealing with: scale, spots, taste, or a softener that quit. Someone who does this work in Midland phones you, usually to book a test.