Water Filter Types 

If you’re like most people, then you probably have some type of water filter in your home, whether it’s a cartridge in a pitcher or a nozzle on a sink.. You’ve also probably heard that the water running through the pipes of most homes is hard, and that your water filter is softening this hard water to make it taste better. The truth is, however, water filtration is not the same thing as water softening, and there are many different types of water filtration methods that take different things out of the water.

The differences between all these types can be complicated and sometimes confusing. This guide aims to explain the different types of water filters in a simple way to clearly lay out the purpose and uses of each type. Knowing this will help you figure out whether you need a water softener or filter, and what kind of filter you need.

Carbon Absorption

The first type of water filter we’ll go over are carbon absorption filters. These are the most common kind sold in stores; the little black dots in the filter cartridges are small pieces of carbon that chemically bond with some of the contaminants in water to remove them. These filters are good for removing dangerous pollutants like asbestos, lead, and mercury, and also bad tasting chemicals like chlorine. Surprisingly, however, they can’t really remove inorganic compounds like arsenic and fluoride.

Carbon filters come in 2 basic types. There are carbon block filters that use a large block of carbon that’s been shaped under high pressure. The water flows through this block, and the carbon removes contaminants. More effective, however, are granulated carbon filters. These work in the same way, but are usually more effective because of the higher surface area of small grains as opposed to one large block.

Here’s a video of a Counter Top Carbon Water Filter so you can see it in action:


Micro-porous Filtration

These are very simple and rudimentary filters that work by passing water through a material with very fine holes such as ceramic. They block solid contaminants like sediments, but chemical impurities make it through; because of this, they’re best used for filtering dirty or muddy water and won’t do much to the water coming out of most pipes

There are three types of these filters called depth, screen, and surface filters. Each serve a different function, but they are all commonly used as pre-filters because they are economical ways to remove almost all of the suspended solids in water.

Reverse Osmosis

These filters act as a compliment to carbon filters. They can remove most of the chemicals left behind by carbon filters such as arsenic and fluoride, and they’re often paired up with carbon filters because they both remove what the other leaves behind. A filter setup like this can be extremely effective if both the reverse osmosis and the carbon filters are high quality.

Reverse Osmosis filters work by pushing water at high pressure through a semi-permeable membrane. This means that the membrane lets some chemicals through, but blocks others. Because of this, however, they should only be used for drinking and cooking water, as they take in a lot more water than they produce.

Water Softening

Water softeners, unlike most drinking water filters, aren’t designed to make water taste better. This is because they’re designed to remove the minerals that make water hard (calcium and magnesium), and these minerals are also what gives water good flavor. They work using an ion exchange process that actually makes water taste salty. The minerals they remove, however, can build up and clog plumbing fixtures, so water softeners are typically used for industrial purposes and not necessarily for drinking and household use.

There are, however, more sophisticated water softeners that can remove the hard water minerals without making the water taste salty. Contractors can install more advanced equipment like this for homes and businesses; Clear Water of San Marcos is a good local company that can set you up with saltless water systems. They even offers several add-ons depending on the filtration jobs you need.


Those are just a few of the most common filter types. There are many more out there, and it’s important to know the differences between them because each one serves a different purpose, and knowing this information can help you make a more informed decision.