Pentair FloPlus Protect 20BB Whole-House PFAS Filter

A cartridge-based whole-house filter that IAPMO lists under NSF/ANSI 53 for PFOA, PFOS, PFHxS, PFNA and PFHpA, for about $325 plus $169 per 40,000-gallon cartridge. Its chlorine claim is Pentair’s own; it is sold through dealers.

Best for Homes with PFAS in the water supply that want every tap treated for a fraction of the cost of a tank-style whole-house system.

Our rating: Fair (3.2 of 5)
Price range: Budget
Verified marks: IAPMO R&T: NSF/ANSI 53 (PFOA, PFOS, PFHpA, PFHxS, PFNA)
Size: One 20-inch housing with a Fibredyne carbon block cartridge; rated 5 gpm and 40,000 gallons; 30 to 90 psi; cold water only

approx. $325 at dealers (Pentair posts no price); approx. $258 on Amazon

See it on Pentair’s site → (opens in a new tab)

We are not affiliated with Pentair. This link goes to the maker’s own page, with no tracking code. How we're funded.

Also sold at Amazon ($258), Fresh Water Systems ($325 for the system (part 150736); approx. $169 for the 655230-43 cartridge), Mid Atlantic Water ($349 for the system) .

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How we evaluated it

How it scores Our rating, metric by metric Fair, 3.2 of 5

Proven reduction 35% of the rating 3 of 5

IAPMO lists five PFAS (PFOA, PFOS, PFHpA, PFHxS, PFNA), tested to 20 ng/L (6 for PFHpA), with 97.5% to 99.8% reduction. No lead, VOC or chlorine listing; its chlorine figures are Pentair’s own tests.
What touches the water 20% of the rating 3 of 5

A polypropylene housing and a proprietary carbon block, with an O-ring that must be seated or it leaks, and a ten-year life on the plastic. No silver is mentioned.
Independent testing 15% of the rating 3 of 5

A paid IAPMO listing with a data table in the manual. No independent test of this model; the one independent study of whole-house carbon filters found PFAS rising after four of eight.
Trust 10% of the rating 3 of 5

A large maker with no recall on water products, but no price on its own site, a manual that warns about chlorine against a spec sheet that claims chlorine removal, and older Prop 65 notices on other filter products.
Running cost & value 20% of the rating 4 of 5

About $325 ($258 on Amazon) and $169 a cartridge, or 0.4 cent a gallon, about a fifth of the HealthShield’s list cost per gallon and two-fifths of its sale cost. At 100,000 gallons a year you change it two or three times, near $420 a year.

The rating, 3.2 of 5, is the weighted average of these scores. See how we rank water filters and our standard.

Where to buy Stores and the prices we saw 3 stores

Amazon (opens in a new tab) approx. $258. The complete system (housing, cartridge, wrench, bracket), shipped and sold by Amazon.com. Three left in stock on 2026-10-23. The replacement cartridge is about $187 there.
Fresh Water Systems (opens in a new tab) approx. $325 for the system (part 150736); approx. $169 for the 655230-43 cartridge. A water-treatment specialist retailer. In stock on 2026-10-23. Pentair sells through dealers and does not publish a price.
Mid Atlantic Water (opens in a new tab) approx. $349 for the system. A water-treatment dealer. In stock on 2026-10-23.

Prices as we saw them on October 23, 2026. They change often. These links carry no tracking code and earn us nothing.

What it’s made of What touches your food, water, skin or air 5 materials

20-inch heavy-duty housing made of polypropylene; Pentair advises replacing the bottom of plastic housings every ten years
Fibredyne carbon block cartridge (655230-43), a Pentair proprietary media
A rubber O-ring (silicone grease is advised) seals the housing; its material is not stated
1-inch female pipe inlet, a pressure-relief button, a mounting bracket and a wrench in the kit
No silver or antimicrobial is mentioned. We found no NSF/ANSI/CAN 372 lead-content listing for it

Who tested it What each test found, and who paid for it 2 tests

Paid certification IAPMO R&T

Lists Floplus Protect 20BB (file W-13717, NSF/ANSI 53-2021, active to 2027-07-29) as a point-of-entry system rated 5 gpm and 40,000 gallons for PFOA, PFOS, PFHpA, PFHxS and PFNA. Pentair’s manual reports PFOA and PFOS cut by 99.82%, PFHxS by 99.39%, PFNA by 98.34% and PFHpA by 97.48%, tested at 5 gpm, 60 psi and pH 7.5 against limits of 20 ng/L (6 ng/L for PFHpA). The maker pays for the program. Open ↗ (opens in a new tab)
Maker’s own test Pentair’s own testing July 2026

Pentair’s July 2026 spec sheet gives chlorine taste and odor reduction of more than 90% for 215,000 gallons at 5 gpm from a 2 ppm challenge, based on internal testing. It is not on IAPMO’s listing. Open ↗ (opens in a new tab)

Who paid, and why it matters

Independent The tester took no money from the maker for it: a consumer group, a journalist, a university or a regulator.
Paid certification An outside lab or certifier tested or listed it, and the maker paid for that.
Maker’s own test A lab report or certificate of analysis the maker commissioned and published.

A certification is a floor, not a verdict: it checks what its program checks and nothing else. We weigh tests by someone with no stake in the result most.

What people ask Worries raised online and elsewhere, and what we found 6 questions

Does chlorine in city water hurt the PFAS filter?: Pentair’s manual says the carbon can be affected by chlorine and that the incoming water may need chlorine removed first. Its July 2026 spec sheet claims more than 90% chlorine reduction from internal tests. The PFAS test conditions in the manual list no chlorine. So the 40,000-gallon PFAS rating may not hold on chlorinated water, and Pentair does not say.
Do whole-house carbon filters let PFAS back through?: In the one in-home study of whole-house carbon systems we found (Duke University, North Carolina homes), PFAS levels in the filtered water rose for four of eight systems (abstract (opens in a new tab)). The abstract does not name the systems. The FloPlus is certified for five PFAS compounds when new, but we found no study of this model. Change the cartridge on schedule.
How often will I be changing it?: More than the “12 months” on the spec sheet. A household that uses about 100,000 gallons a year, our assumption, reaches 40,000 gallons about every five months, so two or three cartridges a year at about $169 each.
Why is there no price on Pentair’s site?: Pentair sells this through dealers, and its site carries a spec sheet, a manual and a cartridge page but no price. We saw the system at $324.85 and $349 at two dealers and $258 on Amazon on 2026-10-23, and the cartridge at $168.71 at the first dealer.
Does the housing leak?: It can, like any plastic housing. The manual warns that an unseated O-ring will leak and strongly recommends replacing the bottom of plastic housings every ten years to avoid water damage. A 2020 ClassAction.org page on leaking under-sink filters names a Pentair Omnifilter owner’s complaint about a split housing, a different product (page (opens in a new tab)).
Has Pentair had chemical or safety notices?: On other products. California’s Prop 65 list shows a 2008 notice from the Center for Environmental Health naming Pentair Residential Filtration over arsenic in water filtration systems, and a 2016 notice naming Pentair over lead in water filter kits, which settled in October 2016. Pentair’s pool division has had separate lead notices, and CPSC has recalled Pentair pool heaters. We found no recall of a water filter.

Trade-offs What to weigh before you buy 4 points

The certification covers PFAS only. Pentair’s July 2026 spec sheet adds a chlorine claim from its own testing (taste and odor, more than 90% at 2 ppm), while its 2024 manual says chlorine can affect the media. Neither is on IAPMO’s listing, and there is no lead or VOC claim.
At 40,000 gallons a cartridge, a household using about 100,000 gallons a year (our assumption) changes it about every five months, about $420 a year at $169 each. Pentair’s spec sheet gives the filter life as about 12 months.
Pentair sells this through dealers and publishes no price. Its site has a spec sheet, a manual and a cartridge page, but we found no page for the system itself. We saw it in stock at two dealers and on Amazon on 2026-10-23.
It is for cold water only, at 30 to 90 psi. The manual says to fit it after the water meter or pressure tank, which usually means plumbing work.

What to know Details worth knowing first

Whole-house filters are usually sold on chlorine. The FloPlus Protect is a cartridge system sold on PFAS, and IAPMO R&T’s directory backs that for this exact model under NSF/ANSI 53. Pentair’s manual gives the test results. Our note on what PFAS are explains why those five compounds are the ones to look for.

It is cheaper than tank-style whole-house systems, and the cost shows up later. A 40,000-gallon cartridge is not much for a whole house, so a household using about 100,000 gallons a year replaces it two or three times a year. Pentair posts no price; its site has the spec sheet and manual, and dealers set the price.

Two cautions. The listing is for PFAS only. Pentair’s newer spec sheet claims chlorine reduction from its own testing, while its manual warns that chlorine can affect the media, so treat the chlorine claim as the maker’s. And a whole-house filter is a poor way to get PFAS-free drinking water if you only need it at one tap. See avoiding PFAS for the cheaper tap-level options.

What we checked Each claim, and how sure we are of it 8 checks

Third-party tested: Yes
Tested by: IAPMO R&T, paid for by the maker

How Pentair FloPlus Protect 20BB Whole-House PFAS Filter measures up against our water filters criteria
What we checked	What we found
Certified, not just claimed Verified	IAPMO R&T’s directory lists Floplus Protect 20BB under NSF/ANSI 53 (file W-13717, active, revised 2026-07-29, to 2027-07-29). Opened 2026-10-23.
Matched to your water Not verified	Not something we can check for you. Read your utility’s PFAS results first. Pentair’s manual says chlorine can affect the media.
The contaminants you care about Verified	PFOA, PFOS, PFHpA, PFHxS and PFNA only, under NSF/ANSI 53. No lead or VOC claim, and chlorine is not on the listing.
Data sheet results Maker’s claim	Percent reductions come from the performance data in Pentair’s manual: PFOA and PFOS 99.82%, PFHxS 99.39%, PFNA 98.34%, PFHpA 97.48%. Pentair’s cartridge page says up to 98% of PFOA and PFOS; its spec sheet says 99.82%.
Chlorine claim Maker’s claim	Pentair’s July 2026 spec sheet lists chlorine taste and odor reduction of more than 90% for 215,000 gallons at 5 gpm with a 2 ppm challenge, from internal testing. It is not on IAPMO’s listing.
Independent test of this model Not verified	None found.
Flow and waste Verified	The listing gives 5 gpm and 40,000 gallons. A cartridge system, so no drain line.
Replacement cost Maker’s claim	Cartridge 655230-43 about $169 at Fresh Water Systems, rated 40,000 gallons. Pentair publishes no price, so this is a retailer’s figure.

What the labels mean

Verified We opened an independent record that confirms it: a certifier’s listing, a regulator’s list or a lab report. It is linked under Sources.
Maker’s claim The maker says so on its own page or label. We read it but found no independent record.
Not verified We looked and could not confirm it, or the maker does not say. Treat it as unknown.

Sources Where our facts come from 9 sources

Pentair FloPlus Protect 20BB PFAS filtration system spec sheet (July 2026). Maker’s page. Published by Pentair. Lists the system, the polypropylene housing, the 40,000-gallon PFAS capacity, the chlorine claim and the IAPMO R&T certification statement. Open ↗ (opens in a new tab)
Pentair FloPlus Protect 20BB installation and operating manual, with performance data. Maker’s page. Revision B, October 2024. Source of the percent reductions, test conditions, the cold-water note, the chlorine caution and the ten-year housing advice. Open ↗ (opens in a new tab)
Pentair FloPlus Protect 20BB cartridge page. Maker’s page. Pentair’s current page for the cartridge. It gives no price and says to contact a dealer. Open ↗ (opens in a new tab)
IAPMO R&T certificate W-13717: NSF/ANSI 53, Pentair Residential Filtration. Certifier or regulator listing. Lists Floplus Protect 20BB and the RainSoft UltreFlo Protect, both point of entry with PFAS claims. Open ↗ (opens in a new tab)
Fresh Water Systems: FloPlus Protect 20BB system. Independent source. Retailer page with the price, 5 gpm and 40,000-gallon rating. The cartridge is listed at $168.71. Open ↗ (opens in a new tab)
Mid Atlantic Water: Whole House PFAS Cartridge Filter (FloPlus Protect 20BB). Independent source. Dealer page for the same system at $349. Open ↗ (opens in a new tab)
Assessing the Effectiveness of Point-of-Use Residential Drinking Water Filters for Perfluoroalkyl Substances (PFASs) (Duke University, 2020). Test report. Abstract read via Crossref. Reports PFAS rising after four of eight whole-house carbon systems. The publisher blocks automated access, so we could not read the data tables. Open ↗ (opens in a new tab)
California Attorney General: Prop 65 notice 2016-00513 (Ecological Alliance v. Pentair, Inc.). Certifier or regulator listing. Lead in water filter kits, filed 31 May 2016; settlement dated 20 October 2016. Open ↗ (opens in a new tab)
California Attorney General: Prop 65 notice 2008-00400 (Center for Environmental Health, Pentair Residential Filtration). Certifier or regulator listing. Arsenic in water filtration systems, filed 26 September 2008; the settlement naming Pentair Residential Filtration is dated 24 October 2008. Not this product. Open ↗ (opens in a new tab)

Alternatives Other options to compare 1 option

Aquasana HealthShield whole-house filter WQA lists it for PFAS and VOCs under NSF/ANSI 53, rated 165,000 gallons. $4,198 list ($2,099 in the fall sale), with a $3,498 tank (half price in the sale) about every two years.

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