Best water filter pitcher of 2025

As mentioned earlier in this article, there are a variety of contaminants worth removing from tap water. The team here in our lab settled on three primary tests to measure the effectiveness of these filters: TDS, pH, and chlorine. Before we began the actual testing process, each jug was removed from the packaging, cleaned and then prepared according to the manufacturer’s instructions. This is very important, as most of these filters use activated carbon filtration, which is what this will do Deposit Sediments settle into the first batches of water you filter if it is not properly cleaned beforehand.

TDS test

TDS stands for total dissolved solids and includes many different impurities found in water. Examples of the most common dissolved solids include “calcium, magnesium, sodium, potassium, bicarbonate, sulfate, chloride, nitrate, and silica,” according to US Geological Survey. In practice, calcium and magnesium deposits in tap water lead to so-called “hard water,” which tastes bad and can be harmful to your health in higher concentrations. (Read more about TDS From the Environmental Protection Agency and US Geological Survey.)

We started our TDS test by mixing an 8-gallon bucket of tap water, measured at 220 ppm TDS, with table salt until we reached a TDS measurement of 300. Generally, 50-150 is considered TDS. Dissolved solids range is ideal for drinking water. We used an Orapxi water quality tester to make these measurements and since the ZeroWater filter includes a TDS tester as well, all TDS readings were verified on both devices. Once our control source was established, we measured one liter of 300 TDS water into each of the water filter jugs and allowed the full amount to pass through the filter.

Once finished, we measured the dissolved solids again and noted the percentage change. This process was repeated for the highest and lowest TDS concentrations, and our results indicate that each of the units we tested was very consistent in removing the same percentage of total TDS from any water passing through it.

Chlorine test

Chlorine in drinking water may seem strange, but it is actually a very common practice in water treatment facilities to add chlorine to the water supply as a disinfectant. This is very effective in getting rid of other, more dangerous contaminants in the water, however World Health Organization estimates A concentration of ~0.2-4 ppm is the standard for tap water, indicating that at least some of it remains after disinfection.

For our testing, we decided to step things up and test water prepared with a concentration similar to that of a swimming pool – 10 ppm chlorine. This gave us a clear indication of the changes after nomination. Again, each filter was tested with one liter of solution and compared to the results of pre-filtration of the water, and again, filters like the ZeroWater significantly outperformed the others.

Test for changes in pH

Finally, during the TDS test, we also measured the change in pH. pH stands for “potential of hydrogen” and is used to measure the acidity of a substance. A pH of zero is very acidic, 7 is neither acidic nor basic, and 14 is very basic. Since the minerals that make up the dissolved solids in tap water increase alkalinity, we expected the filtration process to reduce the pH of the water. In fact, this turned out to be the case, and you can see the table of pH changes below.

Below is a table of the latest TDS removal test results. Data represent the average of three test runs for each filter pitcher.