The 9 types of water filters and when (and where) you should use them

So it looks like you’re finally fed up with drinking contaminated H2O and showering in hard water. I mean, it’s about time there, friend. We’ve all been waiting for you to wake up.

Now comes the arduous task of figuring out which types of water filters are suitable for you and your home. With so many choices ahead of you, I bet you’re thinking, “I wish there were someone out there to help me figure out which water filter I should choose.”

Well, guess what? The water guy is here, as usual, to lead you through the wonderful world of water purification and help you decide which filter is right for you.

Today, I will take you through the many filters available to you and tell you the pros and cons of investing in them. As a bonus, I’m even going to let you know where you should use them, which is pretty essential too.

So pull out whatever you take notes on, fire up the learning portion of your brain, and get ready to learn everything you need to know by the Alex Trebek of filters—me.

Gravity-fed water filter pitchers

The most accessible and portable option for filtering contaminants in your tap water has to be the gravity-fed water pitchers you’ve seen over at your friend’s house. 

Yeah, the water pitcher dispenser you made fun of because it looked weird, and you didn’t realize what it was for. 

Who’s laughing now? 

Your friend is, actually, because they are at home sipping on fancy contaminant-free drinking water while you’re here with me, trying to figure out how to remove physical particles and make the chlorine taste in your water disappear.

How it works:

Gravity-fed drinking water filters operate using a two-chamber system to filter harmful contaminants from your home tap water. The water travels through carbon-based filters between the chambers, filling the pitcher with filtered water for you to enjoy.

Easy, right? 

What’s good about it?

These pitcher-dispensers usually sit comfortably in the fridge and are perfect for those who rent and those who are unable to install a proper water filter system. It’s an excellent little sediment filter to have around the house. 

The filters used in a gravity-fed pitcher usually consist of stainless steel and ceramics combinations, depending on which dispenser you choose, and can be purchased online or from any local department store. 

What’s not so good about it?

The downside to a gravity-fed pitcher is that you consistently have to refill it since the chambers are so small. 

On top of that, you could buy a crappy one and find out that it can only handle a small number of actual chemical contaminants, leaving your water tasting as if it has collected straight from your gutters.

Gross.

Buying a gravity-fed water filter pitcher

If you want a gravity-fed water filter pitcher, have a read of my guide on getting the best ones here: The Best Gravity Water Filter

Faucet-mounted filters

Faucet filters are another excellent choice for renters, with their low-cost price point and easy installation. 

You probably remember them from your grandparents’ house. They hung from the kitchen tap waiting for you to come along and break when you were younger. 

Yeah, that’s the one.

How it works:

This mechanical filter works by attaching to your kitchen sink faucets and filtering tap water as you pour it. When you turn your faucet on, water first passes through a screen. 

The screen captures any sediment, like sand and dirt, before sending the water through compressed activated carbon, which filters contaminants such as chlorine from your water supply. 

What’s good about it?

If you’re like me, easy installation is one of my favorite things to hear, and this one is beyond easy to install. It’s also one of the smallest and most effective filters to replace. 

Saving money is my favorite.

What’s not so good about it?

Drinkers, beware. Faucet filters are super easy to use, but the water supply has to be slowly poured through the faucet filter to be effective. 

To be honest, they are not even that effective. I mean, I don’t want to get down on this filter, but it’s really only suitable for removing chlorine and giving your drinking water a slightly better taste than garden-hose water.

Pass.

Buying a faucet-mounted water filter

If you still really want one of these, check out my breakdown of the best faucet-mounted water filters here: The Best Faucet-Mounted Water Filters

Counter-top filters

Now we’re getting fancy.

Moving up to on-counter filters is like jumping from VHS to DVD. Outstanding clarity and a heck of a lot less plastic.

Counter-top water filters are usually quite portable and don’t require a Bachelor of Arts to put together successfully.

How it works:

Counter-top filters work by connecting directly to your kitchen faucet. The filter housing is filled to capacity when the tap is engaged. The filter cartridge uses granular-activated carbon to remove any volatile organic compounds as it fills, and clean drinking water is pushed through a spout located on the filter housing.

What’s good about it?

Like our first two filter options, counter-top filters are perfect for people who don’t want to pay to install a water filter for their landlords but want to drink water that doesn’t taste like it was stored in steel drums.

Another plus for countertop filters is that they actually do a great job of filtering most impurities from your municipal water supply. 

What’s not so good about it?

What’s the downside to these drinking water filters? They usually look like they were designed by somebody in 1955, imagining what a counter-top filter would look like in 1996. 

They are also tough to match up with specialty faucets, so if you’re rocking some fancy gold faucet taps in your kitchen, you just might be out of luck.

Buying a counter-top water filter

If you’re keen to get your hands on one of these gems, have a read of my buying guide here: The Best Countertop Water Filters

Under-sink water filters

Here’s where we start to level up, my friends. Having an inline under-sink water filter installed in your home means you have now entered the VIP room of filtered drinking water. 

How it works:

Under-sink filters tick quite a few boxes regarding style and filtering abilities. There’s absolutely no wastewater, as this water filter system taps directly into your cold water supply. The system will force water flow through a hose to a plastic filter housing, where the granular activated carbon purifies it, sending it up to your kitchen sink through its own particular faucet.

What’s good about it?

You access highly filtered water every time you turn on your specialized filter faucet, like a powerful water baron from some apocalyptic future, where all the water is super nasty, and you have the only clean, drinkable supply. Under-sink water filters are that cool. 

Another bonus: they are installed underneath your sink, as the name implies. That means no unsightly water filter systems cluttering your countertop or retro tap filters hanging off your fancy faucets. 

What’s not so good about it?

The only strike against installing an under-sink water filter is that they can take up a bunch of space under your sink, as the name implies.

If you prefer using your under-sink area to collect a farm of dust bunnies and almost empty bottles of dishwashing liquid, this may not be the filter for you.

Buying an under-sink water filter

If you’re keen to install an under-sink water filter, make sure you read through my buying guide here: The Best Under Sink Water Filters

Reverse osmosis systems

If you thought drinking water filtered by an under-sink water filter was an elite experience, let me introduce you to the magnificence of reverse osmosis systems.

Many consider reverse osmosis to be the only way to filter drinking water. Installing a reverse osmosis water filtration system puts you in a completely different class of water clarity.

You could charge people to come over and have a filter water sampling party. 

It’s that good.

How it works:

For the reverse osmosis process to work, water flows through a four-stage process to flush out the highest amount of impurities possible. Your cold water passes through a set of sediment and activated carbon block pre-filters. This process filters out dirt, sand, and other organic contaminants that dirty up your water supply by using multiple filters.

Next, the water is sent to the semipermeable membrane, which does all the heavy lifting in the filtration process. The RO system membrane helps remove any health-related impurities and makes the water look and taste better.

The water is then stored in a pressurized tank, keeping the filtered and unfiltered water separate from each other. 

From there, it filters through a final carbon block filter, which removes any remaining odor, such as the stinky egg sulfur smell that your great-aunt Joyce’s water taps make.

What’s good about it?

Look, at this point, I feel like we can be frank. This reverse osmosis water filtration system is the hands-down best. Having a reverse osmosis unit will change your life and is the only way to treat water effectively.

RO system filters are the gold standard for crystal clear, filtered water. In fact, reverse osmosis can remove 13 different types of contaminants, including lead (95-98%), pesticides (up to 99%), arsenic (92-96%), and barium (95-98%).

No more drinking impurities that used to knock off affluent old ladies in the films of the 1930s for you!

What’s not so good about it?

The only catch. 

Reverse osmosis systems can cost a penny and usually need a reverse osmosis water system specialist to be installed correctly, but hey, if you want to drink like a god, you got to pay like a god, right?

Whole-house water filters

So you’re probably still wondering about whole-house water filtration and where they fit in with the water filtration systems mentioned above. 

Many homeowners consider a whole-house water filter as the first line of defense against unwanted contaminants like barium and radium and best at removing sediment and microplastics from the water supply, and the odds are, you already have one.

How it works:

They work by hooking into your direct cold water supply. Water passes through a connected hose and is redirected through a plastic filter housing. 

As the water flows through the housing unit, it’s sent through a carbon block filter that traps the sand, dirt, and other debris that come with a city-supplied water line and then sends the water into your home. 

What’s good about it?

Another plus is that the whole-house sediment filter can allow you to add a water softener straight to your supply. This is where ion exchange takes place, giving way to softer water, which means you can enjoy your showers again. 

Is that why you haven’t been taking them? Yikes.

What’s not so good about it?

The thing against whole-house water filters is that while they can play a part in filtering out chlorine and other contaminants, they don’t do much of a job in reducing odor and improving taste, even if you change your whole house filter regularly. 

In most cases, an additional water filter has to be added to enhance your drinking water.

At that point, it’s like installing two water filters instead of one, and that’s not cost effective and just plain silly.

Like I said before, most homes already have whole-house filters installed, so have a look at your plumbing system to identify if you need to add one or not.

Buying a whole house water filter

If you’re ready to commit all the way and install a whole-house water filter, check out my buying guide first: The Best Whole-House Water Filter

Ultraviolet water filters

There’s no way around it—ultraviolet sounds like a water filtration system that was sent back in time to help us drink better water. 

They sound super high-tech and are very easy to maintain, so it’s easy to see why they attract the attention of 50-year-old bachelors and ultra-lazy water filtration enthusiasts. 

How it works:

The UV water purifier works by taking any potable water supply and using germicidal UV light to destroy the DNA sequences of impurities such as viruses, parasites, and bacteria, making it impossible for them to sneak by and replicate within your digestive system tract.

Yes, I said digestive tract, and you know what happens after that, and it isn’t pretty.

The water is stored in chambers that are exposed to ultraviolet light. This light uses a UV wavelength of 254 nm and, in doing so, can successfully disable bacteria and viruses like E. coli.

What’s good about it?

So yeah, there’s a lot of upside to choosing a UV water filtration system over the rest of your options. From scrambling DNA to its ease of use, an ultraviolet water filter system is a proven way to gain clean drinking water for your home, but before you hop in the car and head over to Kmart, keep this in mind.

What’s not so good about it?

Although ultraviolet water filters eradicate living organisms, they don’t really do a great job with the other impurities in your water supply, like chemicals. Once again, that means you’ll be buying another filtration system to achieve clean drinking water. 

Yeah, right.

You’ll also have to say goodbye to cold water as well, as the ultraviolet light is always on. That means your water is heated as it sits idle. 

Plus, if the power runs out, you’re right back to square one, drinking stinky water and feeling bad about yourself.

No, thanks. I did enough of that in high school.

Distilled water filters

But wait, water guy! My nana always said that distilled water is the way to go!

Give your head a shake, Barb. Your nana is wrong, and you know it.

Having a filtration system like this is comparable to eating a basic salad—you go through the motions and fill up your stomach, but you don’t really get anything out of it. 

How it works:

The distillation process works by taking your cold water supply and boiling it until it becomes steam. The filtration system then cools the steam, returning it to its liquid state, which is then filtered through activated carbon.

What’s good about it?

Distilled water filters are great for taking a massive, undrinkable water supply and getting it to a drinkable state.

What’s not good about it?

If you want the best filtered water available, it isn’t coming from here. You’ll have to replace calcium, minerals, and all that other good stuff.

The problem with distillation is that when the chemical reaction takes place, anything that can’t become steam, like calcium, fluoride, and magnesium (basically all the things in the water that produce health benefits to humans), are lost in the process. 

That’s it, no biggie—just all the essential minerals.

Ceramic water filters

The last water filter I will cover today is one of the most classic filtration methods known—ceramic water filters. 

How it works:

The ceramic water filter is quite classy and is a legendary water treatment technology. You might find that some of the water filters I mentioned above even use ceramic water filters within their systems to help produce purified water. 

Water is poured into the top of the housing units, and the porous nature of the ceramic filters catch contaminants as the water passes through them. There are usually a few levels of filters for water to travel through.

What’s good about it?

Ceramic water filters can produce quality water and remove their fair share of contaminants. It’s a tried and tested filter that has stood the test of time because it gets the job done when it comes to water filtration.

What’s not so good about it?

The extent of that filtration can vary depending on what additional filters are used within the ceramic candle itself. Although most will have an activated carbon filter within it, some don’t, which can make a massive difference in the number of filtered contaminants.

Another negative for ceramic filters is that they are made for portability. Using one for your home is not ideal because they are gravity-fed and can only handle a small amount of water.

Although it is one of the oldest filtration methods, ceramic water filters may have outlived their usefulness.

So that’s it! 

I’ve given you all the different filtration technologies that are available to buy, borrow, or steal from your neighbor and install in your home. You’ll have your own bottled water business in no time!

I’ve given you reviews of the five primary types of water filters that homeowners use to filter their water supply:

  • Gravity-fed pitchers
  • Faucet-fed filters
  • Counter-top filters
  • Under-sink filters 
  • Reverse osmosis systems

I filled you in on the pros and cons of each filter and where they should be installed within your home. Heck, we even talked about which quality water filters are suitable for specific lifestyles.

At this point, I feel like you and I could just sit down and invent the world’s most fantastic water filter or even discover other filtration methods that the universe hasn’t even heard of yet.

Or you could just pick up the reverse osmosis system. That’s probably easier.

Either way, you are well on your way to picking the water filtration system and beginning a water treatment plan that’s right for you.

Good luck, my water purification babies, and may your bottled water business be a success!