Why Is the Alkaline Filter in Your Home Water Purifier Not Working? Causes and Solutions

In a household water purification system, the alkaline filter is a key component in safeguarding drinking water health. By adjusting the pH of water and supplementing it with natural minerals, it ensures every cup has a mild and well-balanced taste.

As a company with 28 years of expertise in the water purification field, UMEK has always adhered to the philosophy of “Technology Safeguards Purity”. From filter material selection to system compatibility, we provide comprehensive protection for household drinking water safety.

If the alkaline filter fails, drinking water will lose its mineral-balancing function. Long-term consumption of water without this adjustment may disrupt the body's acid-alkaline balance and increase potential health risks.

    Figure 1: Alkaline Filter                         Figure 2: Natural Weak Alkaline Ball

When water passing through an alkaline filter does not achieve the expected effect, the main reasons usually fall into three categories:

1.The water flow does not effectively contact the filter media.

2.The filter media has been excessively consumed.

3.The water is not pure enough.

1. Water flow not effectively contacting the filter media
This typically occurs in two cases. One is when the water flow is too high, causing water to pass through the filter too quickly. In such cases, the retention time inside the filter may be less than 0.5 seconds, with water only briefly touching the surface of the filter media before flowing out—leaving no time for effective reaction.

The second case is when unstable water pressure leads to turbulence inside the filter. This turbulence may force part of the water to rush out rapidly without traveling through the intended filtration path.
To ensure effective contact with the media, water flow must remain within the rated range of the filter, and water pressure should stay stable.

2. Excessive consumption of the filter media
This happens because RO water may still contain ions that react with hydroxide ions, leading to rapid depletion of the alkaline filter media. Once the media is consumed, the pH of the output water begins to drop, and the filter can no longer perform its function.
In such cases, it is necessary to either replace the RO membrane to better control feed water quality or use a higher-capacity alkaline filter that matches the water conditions.

3. Impure feed water
If the incoming water contains excessive impurities, residual chlorine, or heavy metals, these will react with the active ingredients of the filter media and reduce its effectiveness. Similarly, high-salinity or high-hardness water can disrupt the media’s dissolution balance, impairing its ability to adjust alkalinity.
These issues should normally be resolved by the RO membrane. If not, it indicates the RO membrane needs replacement to ensure feed water purity.

Additionally, the alkaline filter itself may be of poor quality and may have already lost its function.

At UMEK, every alkaline filter undergoes strict quality control from the very beginning. With rigorous procurement standards, we select only the world’s top filter media suppliers. Each batch of core materials—such as natural weak alkaline balls and high-activity mineral media—undergoes multiple certifications and composition testing. Any raw material with excessive impurities or insufficient activity is rejected.

Thanks to these high standards, the adsorption capacity of UMEK’s filter media is over 30% higher than that of ordinary products. This ensures a stable and long-lasting alkalizing effect, providing households with safe, healthy, weak alkaline mineral water for the long term. It is the preferred choice for families that value quality and safety.

When it comes to water purification, nothing is trivial. Behind every good glass of water lies both high-quality filters and proper maintenance. At UMEK, we firmly believe that “Purity is more than just filtration—it is about attention to every detail.”

Our mission is simple: to ensure every family enjoys water that is “just right” for health. Choose UMEK—make water purification easier, and health more assured.

Contact Information:
Tel: +86 19331305749
Email: sales@cnumek.com / sales@amandawatertech.com
Website: www.amandawatertech.com / www.cnumek.com