Not all water is created equal. There are different amounts of various molecules dissolved in water from different sources. This is measured as Total Dissolved Solids (TDS). There can be acceptable, ideal, and unhealthy amounts of TDS in drinking water.
Reverse osmosis water has a pure and clean taste. This taste is clean because most of the minerals and contaminants that usually make water taste one way or another are removed.
RO water tastes different because it is engineered water. It’s purified to the point where Total Dissolved Solids are dramatically reduced. We need such water purification methods because we live in times where almost none of us has access to pure and untouched mountain spring water.
Can RO water taste bad?
It does not taste bad. It tastes different and that’s a good thing. If your RO purified water tastes the same that the tap water tastes, then there’s a problem. It’s a sign that the RO system is not doing its work. Or – a small chance – but it could also mean that water that is coming from your tap is crystal clear and pure.
However, even RO systems are not bulletproof. If you find RO water tastes funny, then there might be a cause.
Related: Why Does Florida Water Taste Bad?
Testing RO water taste
Do a simple water tasting. Get three same looking clean glasses and fill them with:
1) Your RO water
2) Your tap water
3) Store-bought pure spring water.
You can add one or two more types of water if you wish. Additionally, you can do a blind tasting. For that just invite someone to help you out. The person should give you glasses without telling with water you’re drinking and your job is to tell a difference.
If you’re not doing testing or dedicated water tasting keep in mind a few things. When tasting water you should taste it plain and at multiple times of the day.
The waters don’t really have a strong taste as other drinks do. It’s more a mouthfeel or how it feels in your mouth. Is it a little bit bitter? Does it feel like having some metal in your mouth? Read on to find out the most common water tastes and understand where they come from.
Causes of bad RO water taste and what to do about it
The ideal water to drink has to be in balance. Not too much of things in it but not too little either.
Slight salty taste
This could be the result of abnormally high amounts of salt in the water entering the reverse osmosis system. It could be that people living near the sea somehow get some salty water in the RO systems. Generally, domestic RO systems are not meant to be used with seawater. This process of desalinating sea water with RO technology is possible but requires much more robust equipment.
• Another reason might be that larger than normal levels of salt get absorbed into the ground. It reached the groundwater sources that are supplying wells.
• If you have a water softener, then the water after this treatment will most likely taste a bit salty. Water softeners reduce the so-called hardness of water by introducing Sodium ions. However, water softeners do not purify the water. Softer water will be beneficial for washing and cooking but it’s not ideal for drinking.
• In any case, if salty taste appears, it means that your reverse osmosis system is no longer filtering out contaminants. And the membrane with filters needs to be replaced.
Slightly acidic taste
There’s a difference between sour and acidic taste. Some people are more taste susceptible than others. But you can learn to tell the difference by paying attention to what you taste and how it feels.
Tasting a lemon feels plain sour. Tasting a strawberry that is sweet but has slight acidity to it is quite different. If you’re into third wave coffee you know what all this is about.
However, RO purified water is naturally slightly lower on pH scale thus it can taste slightly acidic. This especially feels if you had something as a snack or a drink that was on a sour side and now are drinking RO water that can taste funny.
If the taste of RO water is clearly sour, then it probably shows a problem in the water purification process. Especially if the unpleasant taste wasn’t there before.
• This happens mostly due to the corrosion of copper tubing if your house was built thirty or more years ago. I have a separate article on why that happens and what to do about it.
• A metallic taste can often be found in groundwater coming from wells. There are plenty of elements in deeper layers of the ground where water forms reservoirs.
One way or another, metallic taste means that TDS is higher than it should be. It could be that sulfates, chlorides, and bicarbonates are informing the taste. Generally, RO deals pretty well with removing these materials, but if this taste appears, maybe the membrane is not doing its job.
Tastes like regular tap water
If you try RO and tap water side by side and there’s no difference, most likely your reverse osmosis systems membrane is no longer filtering out contaminants and needs to be replaced. The membrane is probably ruptured, damaged, or deteriorated. Possibly pre filters were not doing their work so the RO membrane had to work extra hard and it deteriorated sooner. Or maybe two to three years have passed and it’s time to do maintenance and change filters. RO water should taste different than your regular tap water.
Decomposing egg taste & smell
This is caused by high sulfur content in water. This is a serious issue and you should not drink water that tastes awful and is obviously harmful. This could be caused by two reasons.
• Also a long period of non-use and improper sanitizing gives RO water a rotten egg smell. A way to solve this is to wash the system. I have a detailed guide on how to do so.
• Or there was a huge change in your incoming water quality and the RO system is unable to deal with it. In this case, check and taste the tap water. You can also contact your local authorities or municipal water provider for more details.
How do I make my RO water taste better?
So if you just installed a new RO system or replaced filters and membranes for your old one and everything seems fine. But you still don’t like the way your water tastes. Well, my advice is – give it some time. There’s nothing wrong with RO water and is perfectly healthy. Taste is a perception and with the time you can alter your perceptions.
On the other hand, there are simple solutions on how to remineralize your water and change the way it tastes. Even make it a bit more healthy on the way. I have a separate guide on how to do all that. Few extra methods are bellow:
• You can install the remineralization unit in your RO system. Some systems have a final polishing carbon filter that makes water taste even better.
• Try changing the temperature or structure of the water. Drinking it with an ice cube, dropping a pinch of lemon, or even a small pinch of salt will produce changes.
• Pour water and allow it to settle in a jug overnight. It sounds like a superstition, but water molecules act quite chaotically while traveling through the system and all the pipes. So giving water some time might solve the problem.
• Finally, some people like to add a piece of special charcoal into a jug of drinking water. The claim is that it affects the taste of water even further.
If all of this doesn’t scare you, I’d like to suggest you to look into my recommendations for the best countertop Reverse Osmosis systems.