Why Does My Zero Water Filter Smell Like Fish [2024]

Ever noticed a fishy smell coming from your Zero Water filter? You’re not alone, and there’s a reason why this happens. Zero Water filters, like many other water purification systems, use a resin that can release a fishy odour when it starts to break down. This doesn’t necessarily mean the water’s unsafe, but it sure can mess with your senses, especially if you were expecting nothing but clean, fresh-tasting drinking water.

Why Does My Zero Water Filter Smell Like Fish? My Zero Water Filter has a fishy smell likely due to bacterial growth or the breakdown of filter media, which can occur if the filter is not changed regularly or if the water contains organic compounds. Ensuring the filter is replaced according to the manufacturer’s guidelines can help eliminate this issue.

So, what can you do about it? First, check the filter life. These filters aren’t meant to last forever, and their effectiveness can tank dramatically if they’re used beyond their intended lifespan. If your pitcher’s been working overtime and it’s been a while since you last swapped out the filter, it might just be time to replace the filter. Keep an eye on the TDS (total dissolved solids) levels too, as a spike can indicate it’s time for a change. Remember, regular maintenance not only keeps that weird fishy smell at bay but also ensures you’re drinking the cleanest water possible.

Why Does My Zero Water Filter Have a Fishy Smell?

Why Does My Zero Water Filter Have a Fishy Smell?

Ever run into the issue where your Zero Water filter starts giving off a fishy smell? You’re not alone, and it’s enough to make anyone scratch their head or even consider going back to Brita.

Here’s what might be happening: your filter is supposed to snatch up all sorts of contaminants from your water, but when it gets a bit overworked, things can start to get a bit… off.

First up, let’s talk about how long you’ve been using that filter. These filters are champs for a while, but they don’t last forever. If you’ve had the same filter for about a year, or even just over 2 months, it might just be time to replace it.

Filters have a knack for catching and holding onto stuff from your water supply — and not just the stuff you can see. They use a process called ion exchange (and anion exchange for the chemistry buffs out there), which is great at pulling the bad stuff out of your water but can start to leach weird smells if the filter gets too saturated.

Now, if the water tasted fine with a new filter and then started getting funky, it could be a sign that your current filter is on its last legs. It’s tempting to push a filter to its limits to avoid the hassle of getting a new one, but trust me, it’s not worth it. That fishy smell is a big hint that your filter is full and can’t take anymore.

And it’s not just about the smell or even the taste; it’s about the quality of your drinking water. When your water starts tasting or smelling different, it’s a sign that the filter might not be doing its job properly anymore.

Make sure you’re changing your filter every few months, or more often if your tap water is especially hard or filled with contaminants. Also, always wash your hands before touching the filter or the jug—it helps avoid introducing new contaminants.

What Causes the Fishy Taste in My Zero Water Filtered Water?

What Causes the Fishy Taste in My Zero Water Filtered Water?

When you first switch to a ZeroWater filter or start using a new one, the last thing you expect is for your water to start tasting like it came straight out of a fish market.

If you’ve noticed a fishy taste in your filtered water, there are a couple of key factors that might be causing this less-than-pleasant surprise. Here’s a breakdown to help you understand what’s going on and how to fix it.

Bacterial Build-Up

One common culprit behind that fishy taste could be bacteria. When filters are used for a while without being replaced, bacteria can build up and start affecting the taste and smell of your water. This is especially true if the filter has exhausted its capacity to trap contaminants effectively.

Bacteria love moist environments, and a water filter provides just that. If you started using the filter recently and the fishy smell came within the first couple of days or weeks, it might be a sign that bacteria have found a cosy home in your filter.

Chemical Reactions

Another reason might be chemical reactions occurring within the filter itself. For instance, ammonia or substances like trimethylamine, which are associated with decay and can give off a strong fishy odour, might be getting through the filter or even being produced by the breakdown of certain chemicals already caught in the filter.

These substances are notorious for their potent, gross smell, and they can make your whole fridge stink if you store your pitcher there.

Filter Saturation

Your filter’s capacity could also be a factor. Zero Water filters are designed to last until about 007 TDS (Total Dissolved Solids) metre reads, which is roughly equivalent to filtering about 15 gallons of water, depending on the contamination level of your tap water.

If you’ve been using the filter beyond this point, it may not just fail to provide cleaner water; it might actually start to release previously trapped contaminants back into the water.


In conclusion, keeping your Zero Water filter in top shape doesn’t have to be a chore. By understanding the causes behind the fishy smell and taste, you can take proactive steps to ensure your water remains fresh and pleasant. Remember to change the filter every few months or according to its usage and water condition, wash your hands before handling the filter, and don’t let the filter sit unused for long periods which might allow bacteria to grow. If you’ve used Brita or any other filters before, you’ll appreciate knowing exactly when to swap out your Zero Water filter by keeping an eye on its TDS readings and usage. By following these simple guidelines, you can ensure that your drinking water is not only safe but also tastes great, without ever having to worry about unexpected odours or flavours. Discover how a well-maintained water filter can revolutionise your experience, providing consistently clean and great-tasting water.

Frequently Asked Question(Why Does My Zero Water Filter Smell Like Fish)

Why does my filtered water smell fishy?

Filtered water may smell fishy due to the presence of naturally occurring compounds in the water, such as barium or cadmium, or from the breakdown of organic materials. It might also indicate a need to change the filter or clean the system.

How do I know if my ZeroWater filter is bad?

You can tell if your ZeroWater filter needs replacing if you notice a fishy or acidic smell or taste in the water, the water flow slows significantly, or the Total Dissolved Solids (TDS) meter, provided with the pitcher, reads above 006 parts per million.

Can bacteria grow in ZeroWater filter?

Bacteria can grow in ZeroWater filters if they are not properly maintained. While these filters effectively remove dissolved solids from water, stagnant water within the filter can become a breeding ground for bacteria over time. Regular replacement and maintenance are essential for preventing bacterial growth.

Why does my water dispenser smell like fish?

A fishy smell from your water dispenser is often caused by bacteria growth within the unit or the water supply. This can occur due to infrequent cleaning, stagnant water, or issues with the water source itself, necessitating thorough cleaning or filter replacement.

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