Various water filter tests

Published on 15/11/2020 Last updated on 23/10/2023

Tap water is the cheapest way to drink water. The tap water in Europe meets the standards of safety requirements. The quality depends on where the water is extracted, as there may still be small amounts of contamination residues in the drinking water. Would you like to measure the quality of your drinking water? Then there are several water filter tests.

Good quality drinking water equals healthy drinking water. Of course you would prefer that your water is free of unhealthy substances. There are several ways to test the water.

TDS measurement

TDS means Total Dissolved Solids, also known as the total number of dissolved solids in the water. Using a TDS meter you can measure the exact amount of the dissolved solids in the water. In this way you can easily examine how much contamination is present in your tap water. Examples of substances that can be in the water are chlorine, medicine residues, lead, microplastics, asbestos, fluoride and glyphosate. The result of the measurement can be a high or a low TDS value. On average, tap water has a TDS value between 51 and 200. The lower the TDS value, the less dissolved solids there are in the water. A low TDS value benefits the smell and taste of the drinking water. ZeroWater filters the TDS to 0 for really pure water.

Hardness grade

A cloudy coating on freshly brewed tea or limescale deposits in the shower are indications that you have hard water. You can use a test strip to measure the hardness of water. This way you know exactly how much calcium and magnesium there is in your drinking water. You keep this strip in the water for a few seconds. After a minute there will be discoloration in the boxes. Each color box represents a specific value corresponding to a value for the hardness of the water. The hardness of water is measured in German Degrees (° dH). The average water hardness in the Netherlands is 8 ° dH. At lower values we speak of soft water.

pH value test

You can also test the acidity of the drinking water. The acidity of water is expressed in a pH value. The pH scale runs from 0 to 14, with a pH value of 7 considered neutral water. Values ​​below 7 have a higher concentration of hydrogen ions than pure water and are acidic. And vice versa, if the value exceeds 7, there is a lower concentration of hydrogen ions in the water and the water is basic. Ideally, our body tissue should have a pH of around 7.4, or basic. Yet it often happens that our body tissue is acidified. Causes can be poor nutrition, environmental pollution, stress and medicine use. An acidic body is more prone to all kinds of diseases. That is why it is often healthier to drink water with a pH value above 7.5, so that the acidity of our body is lowered, resulting in a more basic body.


Due to excessive fertilization, the nitrate content in groundwater has increased in recent years. This affects our drinking water. In some places in the Netherlands, the nitrate content has already risen above the target level of 25 mg per liter. Nitrate is not directly toxic to humans. However, it can be converted into nitrite and nitroso compounds. In babies, nitrite levels that are too high can cause respiratory distress. In addition, nitroso compounds have been shown to be carcinogenic in animal experiments. You can determine the nitrate content of water by means of colorimetry. Is the nitrate content high? Then use ZeroWater to purify all the nitrate from the drinking water.

Bacterial colony count

For many bacteria, water is the ideal location to grow. Our drinking water naturally contains many bacteria, or microorganisms. You just can’t see them with the naked eye. Not all bacteria are harmful to our health. A common bacteria in our water is legionella, which develops in water with a temperature between 20 and 50 degrees Celsius and often occurs in pipes where water has stood still for some time. Are you curious about which bacteria are present in your drinking water? The number of microorganisms in the water can be determined by performing a bacteria colony count. This research is carried out in a laboratory.