Brondell RF-40 Membrane Water Filter Replacement for Circle Under Sink Reverse Osmosis Filtration System, Lasts 6 Months
$ 89.99
Price: $89.99
(as of Mar 28, 2025 12:01:07 UTC – Details)
The Circle’s reverse osmosis membrane filter reduces contaminants such as heavy metals, cysts, fluoride, arsenic, industrial chemicals, and more. Designed for use with the Circle Reverse Osmosis Under Sink Water Filtration System, which holds Gold Seal Certification by the Water Quality Association (WQA) for reduction of 64 contaminants.
CRYSTAL CLEAR BENEFITS: The reverse osmosis membrane filter separates clean water molecules from contaminants and reduces heavy metals, cysts, fluoride, arsenic, industrial chemicals, and more
WATER QUALITY ASSOCIATION CERTIFICATION: Holds WQA certification for reduction of 64 contaminants when used with the Circle Reverse Osmosis Under Sink Water Filtration System (certified under NSF/ANSI standards 42, 53, 58, and 372)
SIMPLE DIY INSTALLATION: The replacement filter can be installed in just a few minutes with a quick and easy twist and seal installation; The change indicator lets you know when a new filter is needed; Includes filter indicator replacement battery
We design hygiene products that help protect our planet’s essential resources. From water-saving showers and air purifiers to bidets that help reduce toilet paper and energy use, we’re helping you live more sustainably and it feels better already.
Customers say
Customers find the water filter easy to install and maintain. They appreciate its quality and longevity. However, some have reported issues with water content in the filter and packaging. There are mixed opinions on value for money and taste.
AI-generated from the text of customer reviews
11 reviews for Brondell RF-40 Membrane Water Filter Replacement for Circle Under Sink Reverse Osmosis Filtration System, Lasts 6 Months
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$ 89.99
Jason Dalton –
Delivered WET? Don’t freak out.
So, this is the first time I have had to replace my Brondell Reverse Osmosis filter. I have replaced the other pre/post filters twice and now it’ was time to change the RO element. I always dread this part of the cycle on RO systems because it is EXPENSIVE…..but this is how these systems work and deliver clean water. I previously had a GE system… and I used to operate an RO system on our boat (to turn sea water into drinking water). Having dealt with the pre and post filter set several times I noted that these filter come in a box, are individually wrapped and sealed, and are DRY. This time I noted that the RO element seemed heavier. It was in a sealed box and was individually sealed in a pouch as well. When I opened it and took of the cap, liquid dripped out. Initially I was worried that someone had returned a used filter and Amazon sent it back out to me. Even though it seemed to be sealed I wouldn’t put it past a dishonest person to run this back through a bag sealer and return it for the $100 bucks. Then I remembered from my boating days that Reverse Osmosis membranes have to stay wet. When they go for an extended time of no use they must be “pickled” or BRINED in a special storage fluid. I was starting to think these are no different. I hooked it all up, drained the system per the instructions, and tested the water. I was horrified to see that it was producing water that had 290 PPM (parts per million) of TDS (total disolved solids). The water out of the tap was 513 PPM. The water out of my 2 year old RO filter was 80PPM. This was horrible. So, thinking that I might have gotten a used filter, I sent an email to Brondell support. As I waited for a response I decided to run the system through several more flush cycles. This involves running the water out of the resevoir tank until it’s empty, then allowing it to refill (about a 1 hour process). Low-and-behold, each flush revealed a slightly better water test. After I erformed a total of 8 flushes, the Brodell Circle system with all new filters is producing water at about 40PPM TDS. For a reference, good bottled drinking water is about 20-25 ppm TDS. I’m happy with this. After a few days passed I got a response from Brondell support. The verified that the RO filters are indeed shipped wet/brined. They were surpised that it toon so many flush cycles to get to 40PPm…. but I feel SO much better knowing that I am not drinking from someone else’s rotten recylcled filter.I f YOU get a wet RO filter.. and the box seal is in place and the wrapper bag is intact… DON’T freak out. This is how it is supposed to be.BRONDELL…. it might be a good idea to print this on the RO filter box somewhere to allay customer fears (especially since the other 3 filters are shipped dry).The Brondell Circle is a great system. It is so much simpler and the filter cycle and change procedure is indeed much easier that other systems I have had. I feel well assured that the water we are drinking and making coffee from is the best we can get.
Richard Morton –
Easy to replace
Worked in my system. All good.
Isaac Gjefle –
Great product that Amazon is intentionally misleading about
Amazon advertises this item as needing to be replaced every 6 months (the maximum subscription time) but the product itself says it lasts 24 months. Amazon needs to update thier subscription time to match the actual usable time of the product. But they’d siphon less money from your wallet that way, wouldn’t they…
Corrie79 –
Good
Perfect for my reverse osmosis.
haruman –
only filter you can get
Only filter you can get for this system. Filters cost a lot and I wish you can find cheaper replacements. Too bad they made a proprietary system. It ends up costing the end buyer more money. Otherwise filter is what is required by manufacturer.
Joseph Liao –
Works Well Thank You
Theres water inside. Not sure if that means someone used it before I have no way to tell without cutting it open. After i installed it the water is flowing much faster again whereas it was slow with my old membrane with 1 year of usage. After it being clogged after 1 year of usage i decided to swap a new one and instantly the strong water flow came back they advertise 2 years use but i say change it ever if the water flow decreases. Confused to why the new filter came with water inside but since its working i have no complaints.
William F. Lewis –
Brondell water filter
Brondell membrane water filters are of high quality, and are easy to install.
666 –
Works but really should be cheaper/works at recommend time interval
This filter supposes to be good for 2 years before needs changing for 1 household. My house is just 2 mid-age professionals with relative low water usage. However, the filter usually becomes clogs and runs much slower than it should before the 2 year mark.
Linda Wiebe –
RO systemâ¦does great job of filtering our water
Amazon Customer –
Super
Yuriy Pukas –
Filter was used before!! I found full of water inside when open cup, water still going out the filter. Shame on you, fraud!!!