What type of water filter is best?


You deserve to drink only high quality water. So go for the best water filter in the market. No need at all to feel overwhelmed by the wide range of choices available. Read this water filter buying guide to the end and you’ll be confident enough to choose your water filter.

Before suggesting the best water filter you can buy, it pays to know the different types there are in the market and how they work. 

The 6 main types are:

  • Activated Carbon water filters
  • Reverse Osmosis water filters
  • Ultraviolet water filters
  • Mechanical water filters
  • Ion Exchange water filters
  • Ultrafiltration

1. Activated Carbon water filters

This is probably one of the most popular home water treatment systems. The filtering element comprises either granular carbon or a block of carbon.  The carbon must be activated – i.e. treated so as to be more porous. 

Consider that only two teaspoonfuls of activated carbon has an internal surface area that is equivalent to an entire football pitch (about 4000 square metres). The large surface area ensures that a good range of  water contaminants stick to the carbon surface in the scientific process known as adsorption.

Advantages of activated carbon water filters

  • Reduce bad smells in water
  • Boost the taste of water
  • Significantly lowers chlorine levels
  • Fairly inexpensive
  • Easy to maintain
  • Offer natural filtration process

Disadvantages of activated carbon water filters

  • Do not remove chemicals that can’t be attracted to carbon
  • Filtering element stops working properly once clogged
  • Water needs to stay in contact with activated carbon long enough to effectively get rid of contaminants
  • Not effective in removing some pathogenic bacteria and viruses

2. Reverse Osmosis Water filters

Throngs of people glory in this water filtration method as it effectively removes a large percentage of hazardous water contaminants. This is made possible through the 0.0001-micron-rated semi-permeable membrane which only allows water-sized molecules to pass through.

Advantages of Reverse Osmosis water filters

  • Best technology for water softening
  • Most efficient filtration method
  • Enhances taste of water
  • Low energy consumption

Disadvantages of Reverse Osmosis water filters

  • Does not kill pathogenic microorganisms
  • Removes most essential minerals from water
  • Leaves water with acidic pH
  • Lots of reject water
  • Time-consuming – takes up to 4 hours to filter only 10 litres of water
  • Costly installation

3. Ultraviolet water filters

A better term would be UV disinfection. Raw water is subjected to UV light from a UV lamp. All bacteria and viruses in the water are killed when the UV light their DNA.

Advantages of UV disinfection

  • Environmentally friendly – no chemicals used
  • One of the fastest water purification systems
  • Fairly inexpensive to purchase and run

Disadvantages of UV Disinfection

  • They require electricity to function
  • Do not remove dissolved and suspended impurities from water – including rust, pesticides, fluoride, arsenic, turbidity
  • UV light is invisible and so you won’t know if the system is still working properly
  • Works poorly with highly turbid water

4. Mechanical water filters

Call them sediment water filters if you like. And that’s what they simply do. Untreated water is passed through a cartridge or mesh filter that traps any undissolved particles in the water

Advantages of sediment water filters

  • Low cost technology
  • Reduces water turbidity
  • Perfect method to pre-filter water before using other methods like UV disinfection and Reverse Osmosis

Disadvantages of sediment water filters

  • Removes only settleable solids
  • Does not filter out nor kill pathogens
  • Clogging of filters very common
  • Water odour and taste not enhanced

5. Ion exchange water filters

Basically, these systems replace magnesium, calcium and other metal ions in water with sodium. Yes! You read that right. That’s one way to soften hard water.

Advantages of ion exchange water filters

  • Little maintenance required
  • Quick installation
  • Fast filtering time
  • Removes or reduces hardness, nitrates, alkalinity, chloride, sulfates, fluorides, silica, radium, uranium, arsenic, barium, boron, TDS 

Disadvantages of ion exchange water filters

  • Doesn’t get rid of pathogenic microorganisms
  • Filtered water has high sodium content

6. Ultrafiltration water filters

These use a sheet of membrane or hollow fiber to trap water contaminants usually bigger than 0.02 microns 

Advantages of UF water filters

  • Removes some viruses and bacteria larger than 0.02 microns
  • Removes undissolved solids
  • Yields best quality water with least energy consumption

Disadvantages of UF water filters

  • Can’t filter out dissolved solids like Reverse osmosis does

Final Verdict

With this in mind, you will agree that the best water filter for you depends on a number of things:

i) the amount and range of contaminants in your water

ii) taste and odour issues in water

iii) Installation costs

iv) Maintenance requirements

If you take the time to strike a good balance on these factors, your water filter choice should be great. Otherwise, universally speaking, the Reverse Osmosis stands out as the best water filter type because of its capability to remove virtually every contaminant from water.