ZeroWater Filter

If you haven’t heard about ZeroWater, you’re missing out so much! The filters produced by this company are high-quality supplies ideal for the kitchen due to the five-stage technology to get contaminants out of your daily water.

Although, if you’re here, that probably means that you have used these filters in the past and encountered an issue you didn’t expect: an awful fish smell on the water.

There are good news and bad news. The good news is that you’re not alone, as many people have encountered the same problem before. However, the bad news is that getting rid of that smell requires plenty of patience and time.

To understand what causes the fish smell, we have to learn how these water filters work. Let’s start from there.

The ZeroWater Filter, What Is It?

These filters come from the ZeroWater company, which is one of the most popular when it comes to water purification. The ZeroWater filters feature an Ion Exchange system for water filtration, trapping solids from sources like the tap. Additionally, these devices make the water taste pretty good.

Another reason why these filters are great is that they work just fine without us interfering with the plumbing system. The five-step system for filtering water guarantees a safe water source to drink, use in the kitchen, and many other typical purposes around the house.

Here are some of the best products from ZeroWater:

How Do The Five-Step System Work?

During the first filtration stage, the water goes through the coarse filter screen, which features a high-quality infusing carbon micro cloth. As the water passes through the screen, elements like particles and sediments get filtered. Then, the water continues its way to the second stage.

How Do the Five-Step System Work?

For the second stage, the filter has the water going through the foam distributor. This piece is capable of spreading the water all over the filter, which ends up removing many more contaminants out of the water. You could think of it as a secondary filtration system. Then, onto the third stage.

The third stage makes good use of carbon and oxidation, and they work in a system of multi-layers. It may not sound like it, but the carbon is highly capable of reducing pollutants. On the other hand, the oxidation-reduction alloy secures there is no chlorine nor metals in the water.

Those elements mentioned above have another purpose, and that is keeping mold formations away. Or, at least that’s what they should do because one of the reasons for that unpleasant fish smell is that these elements don’t work as they should. We’ll get into this issue in the next section.

As for the next stage, the system filters water through the ION Exchange resin, a dual technology that is one of the reasons why many people like ZeroWater devices. ION Exchange ensures that no ion exists on the water, completely purifying it.

Finally, in the last stage, the filter uses an ultra-fine screen combined with non-woven membrane layers.

These elements do nothing more than delivering the final blow to any contaminant that could’ve survived the previous measures. After this process, your water will be in perfect condition.

The five-stage filtration system ensures there is no chlorine, sediments, ions, and metals, among many other particles that could be dangerous for our health. That’s why these products are a must-have for many people, especially if you care deeply about what you put into your body.

What Is Causing That Fish Smell in the ZeroWater Filter?

There’s no denying of ZeroWater’s efficiency when it comes to purifying water. However, there may come a time when you try to get your water, and for some reason, this unpleasant, fish smell comes out of the filter. What are the reasons that could cause this issue?

What Is Causing That Fish Smell in the ZeroWater Filter?

First, let’s start by saying that while some people have this problem with their ZeroWater, some other customers never get the misfortune of experiencing this.

The fishy smell could originate from several reasons. Nonetheless, the most common one is because the filters usually have anion resins, which are responsible for releasing trimethylamine. That’s what we know as the nasty rotten fish odor.

Of course, the trimethylamine amount that gets released depends on some other minerals and the pH levels present on the water source. While they’re not necessarily bacteria, they do create the perfect combination to create that odor we dislike so much.

That’s why, as we mentioned above, some people notice the odor while some other customers don’t. After checking out comments left by previous customers, it can be said this nasty smell is something that, unfortunately, a lot of people have to experience while using their ZeroWater filters.

Many years ago, the manufacturer actually addressed this issue on their website. It was pretty clear that they were well aware of the problem. However, sometime after that, the company removed any mentioning of the problem. Probably, due to the effect it had on their sales.

How to Get Rid of the Fishy Smell?

Unfortunately, there’s no clear method to remove that odor. By reading opinions from previous customers, many of them have their unique ways of cleaning their filters. After trying the cleaning methods those customers mentioned, the following proved to get rid of the smell for some time.

How to Get Rid of the Fishy Smell?

What you want to do is check the filter. Wash the plastic parts thoroughly by using an ammonia-lemon solution to soak them. Let them rest overnight and then rinse the parts. You may have to replace the filter too.

It’s not a definitive solution, as it is quite possible that the smell returns after a couple of weeks, perhaps it could work for your ZeroWater filter.

Final Words

Fish odor in your ZeroWater filter is not an isolated event. We’d go as far as saying that, under some specific circumstances, it is a problem that you’ll have to face inevitably while using these filters. If you want to avoid it, do regular maintenance on the unit from time to time.

Moreover, if you want a suggestion on which ZeroWater product you should buy, we suggesting this amazing water filter pitcher:

Last update on 2023-03-22 / Affiliate links / Images from Amazon Product Advertising API. WaterFilterly is user-supported. We might receive a commission on any purchase you make through clicking links on this page.

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    1. I just change the filter and presto, no more odor. Change the filter even if less than .006 on meter. I had 1 filter out of 8 that gave that issue. The rest are fine.

  1. If the fish smell has not been noticed before, is it possible the filter just needs to be changed? My 93 year old mother cant remember when she replaced it last, probably more than a year! She has had the system for several years and has not had this issue before. Thanks

    1. This is a problem that I face every other filter. Just threw away a filter that was a month old. It was registering 000 on meter. Going to buy more and try 1 more time. I have the 23 cup dispenser takes up some room in the fridge. Hopefully they willlast longer. I live in a small town that has hard water. The city water is rated as the best in the state. Still get fish smell after a couple weeks. If problem persist will throw away and get bottled water not worth having if nobody will drink it.

  2. Try not filling it ( the water reservoir) up all the way; I noticed that when I stopped filling it more than a little less than half-full, the smell did not occur. It’s not as convenient, but the filters seem to last a heck of a lot longer with no fishy smell.

  3. I used for 3 weeks and actually it started to smells like fish.So I try to find out if only I have this problem or not,and end up finding this website. I live in London,UK. I am glad that I didn’t buy bulk of spare Zerowater filters before Brexit. I do not wish to use this water filter anymore.

  4. I have both the jug and the pitcher. I only get the issue in the pitcher! I switch the filters over after a quick clean and the problem only ever occurs in the pitcher. Could it be that the base of the pitcher is pretty much constantly submerged in the filtered water?

  5. I get the fishy taste in my water in a few weeks of a new filter. Zero Water is an expensive habit. We are on well water.

  6. Ours slowly built up a fishy smell but only when the water was boiled. I thought it was my kettle, but replacing the filter solved the problem. I hadn’t replaced the cartridge for way too long and now have a reminder to replace it at least every 6 months. Now that I know that, I’ll continue to use the product because it does work well.

  7. What causes the bitter taste to the water only had filter one month and half? I use to have a brita and never had a problem with the water??

  8. I have same problems, fishy smell from 10 cup Zero water right after filter was changed. I felt like throw up. I think something wrong with the filter! The company should investigate. I plan to buy a 6 cup pitcher for travel but change my mind.

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