How to choose under sink water filter?

How to choose under sink water filter?

Drinking water is a simple matter, but sometimes it is really a headache.

A few days ago, a friend complained to us that her tap often flows out of yellow muddy water.

I often hear family and friends complain that tap water has a strange smell and the scale is as big as oatmeal after boiling.

There are also problems of pipeline pollution and community secondary water supply pollution reported in the news, which I dare not think about in detail.

In order to drink water safely, many people carry bottled water and barreled water home one after another, which is really tiring after a long time.

Think about buying a water purifier, but the various products and concepts make people confused.

Which one should I buy? Are water purifier kettles and water purifier faucets okay?

Reverse osmosis, ultrafiltration, nanofiltration... What are they?

Come on, as industry experts, we will explain the twists and turns here from principle to purchase at one time.

No matter how fancy the concept and shape are, the core principle of household water purifiers is filtration, which is equivalent to using a sieve to filter out bad substances.

There are currently 4 types of such "sieves":

Microfiltration → Ultrafiltration → Nanofiltration → Reverse Osmosis

The difference is:

Sieve mesh: coarse → fine
Water purification capacity: low → high

Most water purifier kettles and water faucets are microfiltration water purifiers.

The filter element is actually made of PP cotton and activated carbon, and the filtration accuracy is low.

It is cheap, but it can only do simple coarse filtration to remove mud, rust, and residual chlorine.

It has no power against bacteria, viruses, and heavy metals. It cannot be drunk directly and must be boiled before drinking.

Moreover, the service life of the filter element is also very short, and it usually needs to be replaced every 1 month.

Friends who have bought it may wonder: I use a water filter to filter tap water, and the taste has become better?

In fact, the principle behind it is that the sodium and potassium ions in the filter element are used to exchange the calcium and magnesium ions in the water. The water quality has become softer, but you have to take in more sodium for no reason.

Ultrafiltration water purifiers can filter bacteria and viruses in tap water and retain minerals. They do not require electricity or pressure and do not produce wastewater.

The disadvantage is that they cannot filter heavy metals and cannot soften water. If the water at home is hard, there will still be some scale after filtering with it.

The filtration accuracy of the nanofiltration membrane is between ultrafiltration and reverse osmosis. It can remove most bacteria, viruses and heavy metals, and retain some minerals.

The core filter element of the nanofiltration water purifier is the nanofiltration membrane. The nanofiltration membrane removes bacteria and viruses, and then the NSP membrane adsorbs heavy metals to allow minerals to pass through.

Reverse Osmosis Water Purifier (also called RO Water Purifier)

How strong is the purification ability of an RO water purifier?

Almost all substances except water, good or bad, will be intercepted.

Because only water is left, reverse osmosis water purifier is also called pure water machine.

Reverse osmosis technology was first applied to aerospace. Astronauts cannot bring too much water into space, so it is used to filter urine, sweat, and air-conditioning wastewater into drinking water.

However, "Is it good for water to be too clean?" is still controversial.

One school of thought believes that ensuring the cleanliness and safety of water is more important than whether it contains minerals, and food is the best source of minerals.

However, some studies have shown that long-term drinking of "pure water" without minerals may pose health risks. For example, it is easy to cause the loss of calcium, magnesium and other trace elements in food.