Seeking Advice on Water Filtration Systems Altering Water pH and Health Concerns

Hello everyone,

I'm experiencing a puzzling issue with water filtration systems in my area (Non US) and am seeking insights or similar experiences from this knowledgeable community. The tap water here consistently has a pH of 8.0 or above, indicating alkalinity. However, after using various carbon filter-based filtration systems, I've noticed a consistent drop in the pH to around 6.5, which is slightly acidic. This change occurs regardless of the brand or type of filtration system used, including those with carbon filters and even reverse osmosis (RO) systems with water purity around 4ppm.

Initially, the filtered water seems fine, but within days, the pH starts to decrease. Performing a backwash or flushing of the filter cartridges temporarily restores the pH to its original level, but it inevitably drops again after a few days. This cycle repeats, affecting not just the water's taste but also how my body reacts to it, sometimes manifesting as upper right shoulder pain, hinting at possible liver or gallbladder inflammation. Switching to bottled water alleviates these symptoms.

I'm curious if there could be a specific contaminant in our water that, when interacting with the carbon filters, alters the water composition in a way that's not fully mitigated by regular carbon filters or RO filtration. Has anyone else faced similar issues with water filtration systems leading to a decrease in pH and subsequent health concerns? Any advice on addressing this problem or recommendations for specific filtration solutions would be greatly appreciated.

Thank you for your insights!