5 Signs to Tell An Expired Water Filter

how to tell if a water filter has been used

Water filter is common used in our daily life, it benefits us a lot by providing us nearly 100% pure water, while do water filters expire?, and do you know how it get expired? How long is the lifespan? And How to tell an expired water filter? This article will guide you to see the answers.


do water filters expire

What Reduces the Lifespan of a Filter?

Water Quality - The quantity of contaminants in your water affects the life span of a filter.


Water Usage - The number of people the filter serve for, and how often it’s used to work, will directly affect your water usage.


Filter Material - Ion exchange, carbon block, ceramic, mechanical, and nanofiltration are just a few filter types available today, each of them has an expire time.


Type of Filter - Lifespans is various in different types of filters, most filters are vary from sizes, materials, and install locations.


Know Which Water Filter You Own

Knowing what kind of water filter you are using is necessary, it helps you to understand what particles in the water being removed, and knowing the material of it can help to estimate the expiring time. Here are four types of main water filters in the marketing.


how to tell if a water filter has been used
  • Activated Carbon:

Works like a magnet, drag contaminants closer to them, and off the water supply. Its main enemies are pharmaceuticals, pesticide, herbicides, and VOCs.


  • Catalytic Carbon:

Targets chlorine and chloramines.


  • Ion-Exchange or Reverse Osmosis:

Works as a screening mechanism to trap and stop bacteria smaller than 0.01 microns from entering the water supply. And this helps to reduce content of heavy metals prone to lead and mercury, and to remove fluoride.


  • Hollow Fiber Ultrafiltration Membrane

The Membrane has pores that nearly only allow water to flow through the fibers, the pore size is at 0.1 microns, so rationally 99.99999 % of bacteria will be removed, as well as harmful heavy metals, iodine, chlorine, bad odor.


Each type of filter you have might has a different expire date, let’s get a further look at them.


Do Unused Water Filters Expire? If They Do, How Long It Is?

There is no expire for unused water filter on a certain- condition, which is low moisture in the reserving place. With no moisture around the water filter can sit pretty and ready for use any time. While if you want to keep one filter you’ve used once, the water filter might need to be replace after weeks.


How Long Does a Carbon Water Filter Last?

Carbon water filter does have an expiration, while for common family water needs, you won't be worry about frequent replacing for it, you can just replace it in a regular time according to your filtering water valume, as following:

Replacement Period Referrence
1200-1500L 1.5-2 years
4000L 2-3 years
5000L 3-4 years
6000-7000L At least 4 years



How to Tell If a Water Filter Has Been Used?

As we know that all water filter manufacturer don’t determine an expiration date for unused filters, while for a used filter, an estimated lifespan will be tagged on it. And there will be a testing to calculate it.


Before delivering a filtration product to customers, filter producers will run some further tests in the lab, to analyse an exact catalog of removal, and the filter capacity, which is gauged in gallons of water. And to distinguish an expired water filter the following are five signs to help you on it.


5 Signs of An Expired Water Filter

Changed Odor or Smell

Water filter takes over the role to improve the smell and taste of your drinking water - so when your filtered water starts to taste or smell bad, it can be a sign to replace the filter.


As I mentioned among, since we can fast get used to the taste of clean water, when your tap water no longer taste fresh, you can think about it, when did you change your filter?


Slow filtering speed

Flow rate is the clearest indication to show that you need to replace your water filter, all water filters have one common issue, which is the water flow will get affected by them, while you’ll probably get used to it’s changing flow rate, but it is the very sign to tell you it’s time to buy a filter replacement.


how to tell if a water filter has been used

It works for almost all of the water filters, such as an activated carbon water pitcher, or a gravity filter. If the flow rate of a gravity filter gets slower than your kitchen faucet, that is because filtration will become much slower with an expired water filter. You can do some timing tests, timing a few times filtering water through the pitcher and getting an average of the time it needs to filter a full cup. And then compare this average time to the following filtration times to confirm whether your filter lifespan is near to and end.


Slippery water

If your filtered water starts to feel slippery when rubbed between your fingers, that usually means the water is soft. If your tap water is usually soft (high concentrations of sodium and potassium ions) but still feels slippery even after filtering, your filter is no longer functioning and it's time to replace it.


Floaty Bits or Black Mold

You've noticed "floaters" or black mold in filtered water. Black mold is a fungus that can cause many health problems. If you find mold in your filtered water, you need to do a good cleaning of the entire water unit (with a disinfectant), and remember to replace the filter with a new one, as mold spores may also be there.


As an extra precaution, make sure to wash your hands after handling the old filter, as you don't want to contaminate the new filter when you put it in the system.


Metallic Taste or Scale Build Up

You guessed it, hard water. Hard water is caused by the buildup of minerals like calcium and magnesium, which can leave scales on or in the water filter. Also, if your filtered water starts to taste a little metallic, which is also a sign of hard water, it may be time for a fresh water replacement.


To find a reliable water filter supplier, I recommend you Membrane Solutions water filter. We provide the most professional filters in America, our filters all take the class-1 membrane technology, our team has two decades of experience in producing fine filter, dream to provide all human-kind healthy water.

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