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Why Does My Water Smell Like Dirty Socks?

Q: I recently replaced my water filters and now the water smells and tastes bad, or the TDS level is increasing. What's wrong?

A: If you recently changed the filters and/or reverse osmosis membrane and the water now has a bad smell similar to old socks and/or tastes bad, or the TDS level (total dissolved solids) is slowly increasing, it is most likely due to either improper sanitizing of the system or the introduction of bacteria or biofilm during the filter changing process.  This can happen very quickly after a filter change.   See information on sanitizing the water filtration system.   Improper sanitizing or the introduction of bacteria from your hands while handling the filters and/or interior water contact surfaces can introduce bacteria or biofilm into the system. This bacteria will grow, or "bloom" until it causes a foul smell and/or bad taste, or TDS levels approach that of the incoming water. If this occurs the system will usually need to be re-sanitized and new filters installed. Sometimes flushing the system by running a large amount of water can help if it is done in time.