Why does filtered water have bubbles

When a new reverse osmosis system is first installed, or when the filters are changed, there will be air bubbles trapped within the system. These air bubbles will make the water appear cloudy. As these air bubbles dissipate, the water will become clear. Just like the bubbles that you see when you open a bottle of soda, trapped gasses can come out of the water once it is no longer under pressure. Air that is high in oxygen content will often cling to surfaces inside your reverse osmosis, and come out when you fill your glass.

When a reverse osmosis drinking water system is first installed, the filters, tubing, and any other stages that are part of the system will be empty and therefore full of air that can get trapped within the system. Even when the water has been turned on to the system, air bubbles can collect on the walls and fittings of the system, and may not be purged out when the system is first used.

These air bubbles may take a while before they are all cleared, so some cloudy water may occur for a short while. Using a sanitizer when changing the filters of your reverse osmosis system can help to keep the inside surfaces of your reverse osmosis free of particles that allow air bubbles to accumulate.

Also, when changing your reverse osmosis filters, fill the filter housings to the top with water to prevent any extra air pockets when putting the filter housings back on. Support science journalism. Knowledge awaits. See Subscription Options Already a subscriber? Create Account See Subscription Options. Continue reading with a Scientific American subscription. Subscribe Now You may cancel at any time. When I fill a glass of water from my faucet, it looks cloudy.

More importantly, is it safe to drink? When air gets into water supply lines, the pressure of the water forces the air into tiny bubbles and disperses them, making the water appear milky right out of the faucet. To see if air is the issue, fill a glass and set it on the counter. If the cloudiness disappears in a few minutes, tiny air bubbles probably are the culprit—and your tap water is safe to drink. The tiny specks of stone, rock, and soil are present in all tap water at low concentrations, but higher levels can make your water murky.

If your water is from a municipal system, installing an inexpensive sediment filter on your faucet will probably solve your cloudy water problem. The filters use activated carbon cartridges to trap particles that improve the purity and taste of your water. If your water comes from a private well, the cloudy water could have a number of different causes. While the problem might just be air introduced to the lines from the pump or pressure tank, it could also be harmful residue, chemicals, or contaminants inside the well.