Tap water should taste essentially neutral. When it tastes metallic, bitter, earthy, sour, or like a swimming pool, something specific is causing it — and most causes have practical solutions. Here is how to identify what your water is telling you and what to do about it.
Chlorine or Bleach Taste
What it is: Chlorine added by your municipal water treatment plant. Safe but unpleasant. More noticeable in summer when utilities increase chlorination to address warmer water temperatures that accelerate bacterial growth.
How to fix it: An activated carbon filter removes chlorine effectively and inexpensively. A pitcher filter, faucet filter, or under-sink carbon filter will eliminate the taste. Letting water sit uncovered in a pitcher for 30 minutes also allows free chlorine to off-gas, though this does not work for chloramines.
Metallic Taste
What it is: Usually iron, manganese, zinc, or copper leaching from pipes or fixtures. Well water is more likely to have naturally high iron or manganese. City water can pick up copper or zinc from corroding household pipes — especially in newly installed copper plumbing or when acidic water sits in pipes.
How to fix it: Run the cold tap for 30 seconds before drinking to flush water that has been sitting in pipes. For iron or manganese in well water, an iron filter is the proper long-term solution. For copper from plumbing, a reverse osmosis or NSF 53-certified carbon filter handles it at the drinking tap. If the metallic taste is sudden or severe, test your water immediately — elevated copper or lead can indicate a plumbing problem.
Rotten Egg or Sulfur Smell and Taste
What it is: Hydrogen sulfide gas, produced by sulfur-reducing bacteria in well water or released from geological formations. Can also come from a magnesium anode rod in your water heater reacting with sulfate in softened water (in which case only hot water smells).
How to fix it: For well water, an air injection oxidation filter removes hydrogen sulfide along with iron and manganese. For hot water only, replace the water heater’s magnesium anode rod with an aluminum-zinc rod. Shock chlorinating your well addresses bacterial sources temporarily.
Earthy or Musty Taste
What it is: Geosmin and 2-methylisoborneol (MIB) — naturally occurring compounds produced by algae and certain bacteria in lakes and reservoirs. Seasonal algae blooms in surface water sources cause spikes, most commonly in late summer. Completely harmless but can be very strong at very low concentrations (detectable at 10 parts per trillion).
How to fix it: Activated carbon filtration removes geosmin and MIB effectively. If your tap water tastes earthy only during certain months, it correlates with algae seasons in your source water reservoir. A carbon filter — even a basic pitcher filter — will eliminate it completely.
Salty or Brackish Taste
What it is: High dissolved mineral content (high TDS), sodium from a water softener discharge, or saltwater intrusion in coastal aquifers. Also possible from de-icing road salt that has entered groundwater in northern states.
How to fix it: If the saltiness is from your water softener, add a reverse osmosis drinking water system at the kitchen tap — RO removes sodium effectively. For naturally salty groundwater, RO is also the appropriate solution. Coastal well owners may need to consult a hydrogeologist if salt intrusion is severe.
Bitter or Chemical Taste
What it is: Various possibilities: high chloramine levels, disinfection byproducts (trihalomethanes, haloacetic acids), pesticide or herbicide residues from agricultural runoff, or industrial contamination. Worth taking seriously — a persistent chemical taste warrants a lab test rather than just filtering and hoping for the best.
How to fix it: For chloramines, use a catalytic carbon filter (standard carbon is much less effective against chloramines — check your utility’s CCR to see which disinfectant they use). For VOCs and pesticides, NSF 53 certified carbon filters are effective. For unknown chemical contamination, order a comprehensive water test before deciding on treatment.
Fishy or Algae Taste
What it is: Similar to the earthy/musty category, usually algae-derived compounds from surface water sources. Can also indicate barium or cadmium contamination at very low levels. If the taste is new and persistent (not seasonal), test your water.
How to fix it: Activated carbon filtration handles algae-derived taste compounds. If testing reveals barium or cadmium, a reverse osmosis system is needed.
Flat or Plastic Taste from Filtered Water
What it is: Reverse osmosis water tastes flat to many people because RO removes minerals including calcium and magnesium that contribute to natural water flavor. Some pitcher and inline filters have a plastic taste when new that dissipates after the first few uses.
How to fix it: For RO water, choose a system with a remineralization stage (like iSpring RCC7AK) that adds minerals back after filtration. For plastic taste from a new filter, flush the recommended amount of water through the filter before drinking — most cartridges need one to two gallons of initial flushing.
When to Test Your Water
Do not just filter and hope if the taste change is sudden, severe, or accompanied by other symptoms (cloudy water, unusual color, or gastrointestinal illness). These are signs of potential contamination that warrants immediate water testing. Contact your water utility if you are on city water, or order a certified lab test if you are on a well.
Bottom Line
Most funny water tastes have identifiable causes and practical solutions. Chlorine taste needs carbon filtration. Metallic taste needs iron filtration or pipe flushing. Sulfur smell needs an oxidation filter or anode rod replacement. Earthy taste needs carbon filtration. Persistent, unexplained taste changes always warrant a water test before treating.