How to Make Alkaline Water at Home (and Remineralize RO)
September 30, 2026 · 5 min read
The easiest way to make alkaline water at home is to add alkaline mineral drops to a glass of water, though a small amount of baking soda, an alkaline filter cartridge, an alkaline pitcher or a water ionizer will also raise the pH. Whichever you choose, you can check the result with pH test strips or a pH meter. This guide covers each method, how to measure pH, and how the same tools can be used to remineralize reverse osmosis water.
What alkaline water is
pH measures how acidic or basic water is on a scale from 0 to 14. A pH of 7 is neutral, below 7 is acidic and above 7 is alkaline, or basic. Water sold as alkaline typically has a pH somewhere above 8.
A word on health claims: the evidence for health benefits of drinking alkaline water is limited. Your body tightly regulates its own blood pH through the lungs and kidneys, regardless of the pH of what you drink. Many people simply prefer the taste of water with some minerals in it, and that is a fine reason on its own. If you have kidney disease or another medical condition, check with your doctor before changing what you drink.
How to make alkaline water: 5 methods
1. Alkaline or mineral drops
Alkaline drops are concentrated mineral solutions, often made from ingredients such as magnesium, potassium or calcium compounds. You add a few drops to a glass or pitcher following the label. They are inexpensive, portable and easy to adjust, which makes them the simplest way to prepare alkaline water. Some drops are sold mainly to remineralize water rather than raise pH, so read the label for what you want.
2. Baking soda
Baking soda (sodium bicarbonate) is alkaline, and a small amount dissolved in water will raise the pH. Start with a small pinch in a large glass or pitcher, stir until dissolved, and test. More is not better: too much gives water a salty, soapy taste.
Baking soda adds sodium. If you are on a sodium-restricted diet, have high blood pressure, or have heart or kidney problems, skip this method or ask your doctor first.
3. Alkaline or remineralizing filter cartridges
Remineralizing and alkaline cartridges are inline filters, usually installed after the last stage of an RO system, that dissolve minerals such as calcium and magnesium into the water as it passes through. They raise the pH somewhat and add minerals without any daily effort. Cartridges wear out over time, so they need replacing on the manufacturer's schedule.
4. Alkaline pitchers
Alkaline pitchers work like a standard filter pitcher but include a mineral cartridge. You fill the pitcher, wait for it to filter, and pour. They are affordable and need no installation, but they hold a limited amount and the cartridge needs regular replacement.
5. Water ionizers
Water ionizers use electrolysis to split incoming water into a more alkaline stream and a more acidic stream. They are the most expensive option and need a countertop or under-sink spot and power. Ionizers depend on minerals already in the water to work, so they generally perform poorly on very low-mineral water like RO water unless minerals are added first.
Comparing the methods
| Method | Upfront cost | Effort | Notes |
|---|---|---|---|
| Alkaline or mineral drops | Low | A few drops per glass or pitcher | Easy to adjust; portable |
| Baking soda | Very low | Measure and stir | Adds sodium; can taste salty |
| Remineralizing cartridge | Moderate | Install once, replace periodically | Hands-off; pairs with RO |
| Alkaline pitcher | Low to moderate | Fill and wait | Limited capacity |
| Water ionizer | High | Install; needs power | Needs minerals in the water |
How to measure pH at home
- pH test strips. Dip a strip, wait, and compare the color to the chart. They are cheap and fine for a rough reading. Choose strips made for drinking water, since very low-mineral water such as RO water can give unreliable readings on some strips.
- Digital pH meter. More precise. Calibrate it with the buffer solutions it comes with, rinse the probe between samples, and store it as the maker directs.
Test after you add drops or baking soda, and test again later if you store the water, since pH can drift as the water sits open to the air.
pH and TDS are different measurements. TDS tells you how much is dissolved in the water, and pH tells you how acidic or basic it is. See what TDS in water means.
Why RO water tests slightly acidic
Reverse osmosis water often reads a bit below neutral on a pH test. That is normal and has two simple causes:
- Dissolved carbon dioxide. The membrane removes minerals but not dissolved carbon dioxide gas. CO2 in water forms a weak acid, which nudges pH down.
- Fewer buffering minerals. In tap water, dissolved minerals such as bicarbonate act as a buffer that resists pH change. With most of those removed, even a little CO2 has a noticeable effect on the reading.
This does not mean RO water is harmful. Its low mineral content also means its pH changes easily, which is why a few drops of minerals can shift it quickly.
How to remineralize reverse osmosis water
To remineralize reverse osmosis water, use the same tools above: mineral drops for a glass or pitcher, an inline remineralizing cartridge after the RO stage, or a mineral pitcher filled with RO water. Many people do this for taste, since RO water can taste flat. Baking soda adds sodium rather than calcium or magnesium, so it raises pH but is not really remineralization.
Start by knowing your water: a free water test gives you a TDS reading (a mailed kit anywhere in the U.S., or in person in Northern Virginia), and a pH strip covers the rest.
Where the Hydra fits
The Sanavia Hydra is a tankless under-sink reverse osmosis system with five stages: sediment, carbon, carbon block, reverse osmosis membrane and post-filter. The fifth stage adds some minerals back after the membrane, so the water isn't stripped bare. If you want it more alkaline or more mineral-rich than that, add drops or pour it through a mineral pitcher.
In independent accredited lab testing of an Arlington, VA home's tap water, total trihalomethanes fell from 58 ppb to 2.79 ppb after the Hydra, a 95% reduction (see the results). The Hydra is $999 to self-install or $1,250 professionally installed in the DC, Maryland and Virginia area, with free U.S. shipping, 60-day returns and a 3-year warranty. For more on RO basics, read what reverse osmosis water is.
Frequently asked questions
The simplest way to make alkaline water at home is to add alkaline mineral drops to water. You can also dissolve a small pinch of baking soda, use an alkaline pitcher or remineralizing filter cartridge, or use a water ionizer. Check the result with pH strips or a pH meter.
The evidence that alkaline water is better for you is limited. The body regulates its own blood pH through the lungs and kidneys regardless of what you drink. Many people drink it simply because they like the taste; ask your doctor if you have a medical condition.
Yes, a small amount of baking soda dissolved in water will raise its pH. Start with a pinch and test. Baking soda adds sodium, so people on sodium-restricted diets or with heart or kidney problems should skip it or ask a doctor first.
Reverse osmosis water often tests slightly acidic because it still contains dissolved carbon dioxide, which forms a weak acid, while the minerals that would normally buffer pH have been removed. This is normal and easy to adjust with mineral drops.
Yes. The Hydra's fifth stage already adds some minerals back after the membrane, and its water is a clean base if you want more: add mineral drops or pour it through a mineral pitcher, then check the pH with a test strip or meter.
