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Do Reverse Osmosis Filters Remove Fluoride?

By: David Trinh
Last Updated:
reverse-osmosis-filters

If you know that your tap water contains fluoride, there’s a good chance you’ve been interested in learning how to remove it.

One solution that many homeowners turn to is reverse osmosis filters.

Do reverse osmosis filters remove fluoride?

The short answer is: yes, reverse osmosis removes around 80-90% of fluoride.

Below, we’re covering how reverse osmosis (RO) removes fluoride from water and we will even touch on just how much fluoride you can expect a RO filter to remove.

Then, we’ll go into the other contaminants that it may be able to remove and some of the downfalls you should consider before getting one of these filters. We’ll end with our recommendations on finding the right reverse osmosis filter.

How Does Reverse Osmosis Work?

Reverse osmosis filters are one of the most effective means to clean water.

Their reverse osmosis membrane, in conjunction with additional filters, traps any contaminants that are bigger than H2O particles.

So how does RO do it exactly?

The reverse osmosis system works by forcing water through its semi-permeable membrane at high pressure.

Here, it has very small pores that will allow water to slip past but will stop any larger molecules in their tracks. The water that gets trapped in the filter due to contaminants is then purged from the system, leaving only clean and purified water behind.

RO filters continue this process constantly, forcing water into a chamber, then through the reverse osmosis film and sending wastewater out through the drainpipe.

Fluoride is much bigger than water, so it is one of the contaminants that will get removed with wastewater as the reverse osmosis system works.

How Much Fluoride Is Removed Through Reverse Osmosis?

average-removal-of-fluoride

The amount of fluoride removed from water through reverse osmosis will depend on the specific membrane being used, but the results are typically good.

The Water Quality Association’s helpful fluoride infographic shows an average of 80-90% removal of fluoride from drinking water when a reverse osmosis filter is used.

Compared to other filtration systems, this is likely the best rate of removal you’ll get for fluoride.

This is exactly why so many people turn to RO filters when removing fluoride is their ultimate goal.

Does Reverse Osmosis Remove Other Contaminants?

removes-contaminants

Yes, RO filters get rid of other unwanted contaminants from water.

According to the Encyclopedia of Food Sciences and Nutrition, RO filters are effective at removing as much as 99% of natural contaminants, like viruses and bacteria.

If you need to treat unclean water before you feel safe drinking it, then using reverse osmosis filters would be a great way to do it. Additionally, they can also remove 95% of inorganic compounds like chlorine, lead, sodium chloride, calcium, and magnesium.

Reverse osmosis filters work by breaking up the filtration process into multiple stages, with the RO filter being just one of them.

For example, many RO filters also use carbon filters to remove chlorine particles before the water gets to the RO membrane, as these particles can damage the membrane.

Below are just some of the contaminants that reverse osmosis removes:

Protozoa, bacteria, viruses, sodium, chloride, copper, chromium, lead, arsenic, fluoride, radium, sulfate, calcium, magnesium, potassium, nitrate, and phosphorous.

Risks of Reverse Osmosis Filtration

There’s no perfect way to filter water, so it’s only fair to go over the potential downfalls of this type of filtration system. While you may not experience all of these, it’s important to note them before you make your final decision on whether to buy one for use at your home.

Regular Maintenance

maintenance

It’s typical for a RO filter to utilize three to four filter stages to fully treat the water. Unfortunately, these filters don’t all have the same lifespan. That means that these filters will need to get swapped out and replaced at varying intervals while in use.

Some filters may last for six months, while others can last a year.

The reverse osmosis membrane itself can last for about two years without needing to be replaced, but you’ll still need to change out the filters that don’t last as long. If you don’t, the system may not work as effectively or may get clogged.

Pricey to Use Over Time

expensive

Reverse osmosis filters are incredibly successful at creating clean, drinkable water. Because they’re so effective, you’ll find that these filters are much more expensive than other water filters designed to remove fluoride.

First, you’ll face a higher up-front cost for the filter itself, and then you’ll still need to pay to replace the individual filters throughout each year. This can make purchasing a reverse osmosis filter less accessible to some people.

Water Waste

waterwaste

A lot of RO water filters have a 4:1 wastewater to clean water ratio, meaning you’re getting rid of a lot of the water that is originally forced through the filter.

If you’re concerned with water usage or live in an area where there is a drought, you may not enjoy this wasteful aspect of the filters.

You can try to find RO systems that aren’t quite as wasteful with ratios closer to 2:1 or even 1:1, but you won’t have any luck finding a system that eliminates waste water altogether.

Leaves Drinking Water Without Minerals

drinking-water

RO filters are incredibly thorough. While it’s a benefit when it comes to removing fluoride, it also means that it may remove important minerals like magnesium and calcium.

Such minerals, when present in water, give it a more neutral, alkaline taste. Without them, you may find that the water tastes a bit acidic. If you find this taste not to your liking, you might prefer adding a remineralizer filter to put these healthy minerals back in for a better flavor.

Picking a Reverse Osmosis Filter

If you’ve considered all of these downsides and still feel confident that a reverse osmosis water filter is the right fit for you, here’s what you should keep in mind during your buying decision:

Do I Want an Under-Counter or Countertop Model?

Most models are made to go beneath the sink to be kept out of the way. However, if you don’t want to sacrifice your sink cabinet space, you may be able to find a model that sits on the countertop or the ground. You’ll find that these models are usually smaller.

Do I Want to Get Rid of Additional Contaminants As Well?

Are you only focused on removing fluoride, or do you care to remove other contaminants also? If there are certain organic or inorganic contaminants that you specifically want to eliminate, you may want to perform additional research to ensure the RO filter you choose targets these.

What Budget am I Working With?

Be prepared – an RO filter is going to cost more than the other options on the market. Some can exceed even $1000. You can certainly find models at a lower price point, however. Focus on the $250-1000 range for a model that works well while still saving you money. 

Am I Looking for a Tankless or Tank Version?

RO systems with tanks will filter your water ahead of time and hold onto the clean water so you always have access to it, while tankless systems can save space but will take a bit longer to produce clean, filtered water.

Do I Prefer a Specific Maker?

There are tons of great RO filter brands on the market, and we’ve reviewed the best RO systems and brands in our main guide.

If you check our reverse osmosis systems review page you can do your own research to determine which brand may be the best for your home water needs.

If you’re just looking for a fluoride-specific filter, check out our fluoride filters review.

Final Thoughts

Do reverse osmosis filters remove fluoride?

Yes, and quite impressively.

While these filters are more expensive than other fluoride filters on the market, they’re also one of the most effective ways to treat water.

Spend some time looking into the RO filter options on the market, and you’re sure to find one that meets your needs at a price within your budget.

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AUTHOR
David Trinh
David is an expert in all things plumbing, heating, cooling, and water treatment. He got his start in the plumbing business working on fixing all types of home improvement issues including water leaks, broken toilets, appliance installation, and more. Over time, he learned a ton about installing and choosing the correct water treatment products for homeowners. He nows spends part of his time servicing local clients and part of his time educating consumers about water treatment and other household appliances.