Reduces trace dissolved iron and metallic taste from well water. Genuine Pentek housing, RFFE20-BB iron cartridge, bracket & wrench. Light iron polishing only.
Watch This Before BuyingMeet Aidan, your water treatment expert
Reduces trace dissolved iron and metallic taste from well water. Genuine Pentek housing, RFFE20-BB iron cartridge, bracket & wrench. Light iron polishing only.
Watch This Before BuyingMeet Aidan, your water treatment expert
Not sure if a cartridge iron filter is right for your water?Call Aidan with your water test results and he will tell you whether this trace iron cartridge fits your situation, or whether your iron level, type, or pH means you need a backwashing iron filter instead. No guessing, no upselling.
✓ Genuine Pentair Pentek 20" Big Blue filter housing (model 150233), high-flow polypropylene with a built-in pressure relief button
✓ Pentek RFFE20-BB radial flow iron reduction cartridge (4.5" x 20"), pre-installed, with iron oxidizing media in a radial flow design for maximum contact time
✓ Heavy-duty steel mounting bracket with hardware
✓ Filter wrench for easy cartridge changes
✓ Free shipping to all lower 48 states
Important honesty note: this cartridge is a light iron polishing filter for dissolved (clear-water) iron only. It is rated for up to 3 ppm dissolved iron under ideal conditions, but practical cartridge life drops significantly above 1 ppm for a family. It does not handle ferric (red/rust) iron, iron bacteria, or hydrogen sulfide (rotten egg smell). If your iron test shows more than trace levels, or you see red/orange water, you need a backwashing iron filter instead.
Protect the cartridge: a 20" Big Blue sediment filter installed upstream keeps sand, grit, and rust particles out of the iron reduction media. Pentair recommends pre-sediment filtration for best results.
Filter Housing
Manufacturer
Pentair (Pentek)
Model
150233 Big Blue
Housing Dimensions
approximately 7" x 7" x 21"
Connection Size
1" NPT female (inlet and outlet)
Housing Material
High-Flow Polypropylene (HFPP)
Max Operating Pressure
90 PSI
Pressure Relief
Yes, built-in button on the cap
Certification
NSF/ANSI Standard 42
Made In
USA
Included Iron Reduction Cartridge
Cartridge
Pentek RFFE20-BB (part 155263-43)
Cartridge Size
4.5" x 20" (standard Big Blue)
Media
Iron Oxidizing Media, radial flow design
Reduces
Dissolved (ferrous / clear-water) iron up to 3 ppm
Capacity at 1 ppm iron
80,000 gallons
Capacity at 2 ppm iron
40,000 gallons
Capacity at 3 ppm iron
26,000 gallons
Peak Flow Rate
10 GPM
Nominal Filtration
25 micron
Temperature Range
40°F to 125°F
Certification
NSF/ANSI 42 (material requirements)
Water Quality Requirements
pH
Greater than 7.0 (neutral to alkaline water)
Iron Type
Dissolved (ferrous / clear-water) iron only
Max Iron
3 ppm (practical for a family up to ~1 ppm)
Manganese
Less than 1 ppm
Iron Bacteria
Must NOT be present (shock-chlorinate first)
Hydrogen Sulfide
Must NOT be present
This is a polishing filter, not a primary iron treatment. If your water test shows iron above 1 ppm, ferric (red/orange) iron, iron bacteria, hydrogen sulfide, or pH below 7.0, this cartridge is the wrong tool. A backwashing iron filter with Katalox Light media handles those conditions properly and regenerates itself, so you never have to replace a $40+ cartridge every few months.
Cartridge Life by Iron Level and Household Size
Iron Level
1 person (75 GPD)
1 ppm
about 1,067 days
2 ppm
about 533 days
3 ppm
about 347 days
Iron Level
Family of 4 (300 GPD)
1 ppm
about 267 days (9 months)
2 ppm
about 133 days (4-5 months)
3 ppm
about 87 days (under 3 months)
Reality check: at 2-3 ppm iron for a family, you are replacing this cartridge every 3 to 5 months at $40 to $60 each. A backwashing iron filter pays for itself within the first year and regenerates automatically. This cartridge makes economic sense only for trace iron below ~1 ppm.
Most homeowners install this filter in under 1 hour. No electricity, no drain line, and no programming. Basic plumbing skills and a pipe wrench are all you need.
1Turn off the water and relieve pressure: shut off the supply (or the well pump at the breaker) and open a faucet to drain residual line pressure.
2Mount the bracket: secure the steel bracket to a wall stud with at least 8" of clearance below the housing so the sump can drop down during cartridge changes.
3Install a sediment filter first (recommended): Pentair recommends a 20" Big Blue sediment filter upstream to keep particulates out of the iron reduction media.
4Connect the plumbing: thread the 1" NPT connections into the housing head with Teflon tape, following the IN and OUT direction marked on the cap.
5Turn on and flush: open the water slowly, press the pressure relief button to bleed air, then run water for at least 20 seconds before drinking or cooking use. Some carbon fines (fine black powder) may flush at first.
Correct installation order (well water): Well → Pressure Tank → Sediment Filter → Iron Reduction Filter (this unit) → Carbon Filter or Water Softener → UV. This goes after sediment so grit does not clog the iron media. See the complete iron filter guide →
Not sure this is the right iron solution? Call or text Aidan at 800-460-5810, 7 days a week. Send your water test results and he will tell you honestly whether this cartridge fits your iron level or whether a backwashing iron filter is the right tool.
Replace the Iron Reduction Cartridge Depends on iron level
The RFFE20-BB does not regenerate. Once the iron oxidizing media is exhausted, it stops reducing iron and must be replaced. At 1 ppm dissolved iron for a family of four, expect roughly 9 months of life. At 2-3 ppm, that drops to 3 to 5 months. Monitor your water for returning iron stains or metallic taste as the signal to change.
Inspect the Housing O-Ring During each cartridge change
With the sump off, check the large O-ring on the housing head for cracks or flat spots and wipe it clean. A thin coat of food-grade silicone grease keeps it sealing well. Press the pressure relief button before unscrewing the sump so the housing is not under pressure.
Watch Your Pre-Filter Ongoing
If you run a sediment filter upstream (recommended), keep up with that cartridge too. Sediment reaching the iron media shortens its life and can cause channeling.
Cost reality check: a genuine RFFE20-BB replacement cartridge runs $40 to $60. At 2-3 ppm iron for a family, that is $80 to $240 a year in cartridges. A backwashing iron filter regenerates automatically, handles much higher iron levels, and costs nothing in consumables. This cartridge makes economic sense only for trace iron (~0.5 to 1 ppm).
"Great information and support, delivered promptly, straightforward installation, questions answered. What more can you ask for." ★★★★★
Allen L., Verified Buyer
"Great support from Aidan. I did this myself with iron filter, water softener, and carbon tank. Be careful with the outflow connections, I had to use tape and dope to stop a drip." ★★★★★
Derek C., Verified Buyer
"Mid Atlantic Water was very helpful and always answered my questions quickly. This system saved me thousands over what other companies recommended." ★★★★★
Verified Buyer, Verified Buyer
Video Guides
Watch: Iron filters for well water, the complete guide has 32 years of industry experience.
Iron Filters for Well Water: The Complete Guide
Trace Iron Polishing for Well Water With Low Dissolved Iron
Genuine Pentair Pentek Big Blue housing with an RFFE20-BB iron reduction cartridge, 1" NPT connections, and NSF/ANSI 42 certified components.
The 20" Big Blue Iron Reduction Filter Kit is a whole-house cartridge iron filter built around a genuine Pentair Pentek 150233 Big Blue housing and a Pentek RFFE20-BB radial flow iron reduction cartridge. It is designed for well water homes with trace to low levels of dissolved (ferrous / clear-water) iron, typically 0.5 to 1 ppm, where a full backwashing iron filter is more system than you need.
The RFFE20-BB uses an iron oxidizing media in a radial flow design that maximizes contact time between the water and the media. As dissolved iron passes through, the media oxidizes and traps it. The cartridge is rated for up to 80,000 gallons at 1 ppm iron and supports a peak flow rate of 10 GPM. But capacity drops sharply at higher concentrations: 40,000 gallons at 2 ppm and only 26,000 gallons at 3 ppm.
Be clear about scope. This is a light iron polishing filter for clear-water dissolved iron only. It does NOT handle ferric (red/rust/particulate) iron, iron bacteria, hydrogen sulfide rotten egg smell, or iron above practical trace levels for a family. It requires pH above 7.0 and manganese below 1 ppm. For iron above 1 ppm, for any visible red or orange iron, or for combined iron and sulfur, a backwashing iron filter with Katalox Light media is the right tool, handles dramatically more iron, regenerates itself automatically, and costs nothing in consumables. If you are not sure which your water needs, call Aidan with your water test results and he will tell you honestly.
✔Dissolved Iron Up to 3 PPM
✔80,000 Gal at 1 PPM
✔Radial Flow Design
✔Genuine Pentek RFFE20-BB
✔10 GPM Peak Flow
✔1" NPT Full Flow
✔Complete Kit
Feature
Our System
Others
Housing Brand
✔
Genuine Pentair Pentek
Generic / No-Name
Iron Cartridge
✔
Genuine Pentek RFFE20-BB
No-Name Iron Media
Flow Design
✔
Radial Flow (max contact time)
Axial Flow (channeling)
Iron Capacity (1 ppm)
✔
80,000 Gallons
Unrated / Low
Peak Flow Rate
✔
10 GPM
5 GPM or Unrated
NSF Certification
✔
NSF/ANSI Standard 42
Not Certified
Connection Size
✔
1" NPT (Full Flow)
3/4" (Restricted)
Pressure Relief Button
✔
Built-In
Not Included
Bracket + Wrench
✔
Included
Sold Separately
Housing Brand
✅ UsGenuine Pentair Pentek
❌ ThemGeneric / No-Name
Iron Cartridge
✅ UsGenuine Pentek RFFE20-BB
❌ ThemNo-Name Iron Media
Flow Design
✅ UsRadial Flow (max contact time)
❌ ThemAxial Flow (channeling)
Iron Capacity (1 ppm)
✅ Us80,000 Gallons
❌ ThemUnrated / Low
Peak Flow Rate
✅ Us10 GPM
❌ Them5 GPM or Unrated
NSF Certification
✅ UsNSF/ANSI Standard 42
❌ ThemNot Certified
Connection Size
✅ Us1" NPT (Full Flow)
❌ Them3/4" (Restricted)
Pressure Relief Button
✅ UsBuilt-In
❌ ThemNot Included
Bracket + Wrench
✅ UsIncluded
❌ ThemSold Separately
✔ Free Lifetime Tech Support
Every product we sell comes with free technical support for life. Questions about cartridge life at your iron level, when to upgrade to a backwashing filter, or how to fit iron treatment into the rest of your train? Call, text, or email anytime.
📞 Call Us800-460-5810
✉️ Email Supportsupport@midatlanticwater.net
🕒 Live Hours7 days a week
Frequently Asked Questions
It reduces dissolved (ferrous / clear-water) iron up to 3 ppm, the metallic taste iron causes, and some sediment down to 25 micron. It does not reduce ferric (red/rust) iron, iron bacteria, hydrogen sulfide, manganese above 1 ppm, or hardness. Those need a backwashing iron filter.
No. This is a light iron polishing filter for trace dissolved iron only. If your iron is above 1 ppm, if you see red or orange water, or if you have iron bacteria or sulfur smell, a backwashing iron filter with Katalox Light media is the right tool. It handles dramatically more iron, regenerates automatically, and costs nothing in consumable cartridges.
It depends on your iron level and water usage. At 1 ppm iron for a family of four (about 300 gallons per day), roughly every 9 months. At 2 ppm, every 4 to 5 months. At 3 ppm, under 3 months. Monitor for returning metallic taste or orange stains as the signal to change.
Clear. The water must run clear from the tap. If you see any orange, red, or rust color in the water, that is ferric (particulate) iron and this cartridge cannot handle it. You need a backwashing iron filter instead.
Yes. The RFFE20-BB requires pH above 7.0 (neutral to alkaline). If your water is acidic (pH below 7), the iron oxidizing media will not work properly. You either need an acid neutralizer upstream first, or a backwashing iron filter that is designed to handle low-pH iron.
Pentair recommends pre-sediment filtration for best results. Installing a 20 inch Big Blue sediment filter upstream keeps sand, grit, and rust particles out of the iron reduction media and extends cartridge life significantly.
No to both. This is a passive cartridge filter with no power, no drain line, and no programming.
Upfront yes ($329 vs $1,200+). But if your iron is above 1 ppm, you will replace the cartridge every 3 to 5 months at $40 to $60 each. That is $80 to $240 a year in consumables. A backwashing iron filter costs more to buy but regenerates automatically and has zero ongoing cartridge cost. It pays for itself within the first year at moderate iron levels.
20" Big Blue Iron Redu...$329.00
Trace Iron Polishing Done Right
A genuine Pentek housing and RFFE20-BB cartridge for $329, with honest limits stated upfront.
The problem with no-name iron cartridges
No-name iron cartridges use generic media with unknown capacity, thin housings that crack under pressure, and axial flow designs that allow channeling so water slips past the media without treatment. Worse, they are sold without any honesty about what a cartridge iron filter can and cannot do, so buyers expecting it to fix serious iron problems are disappointed.
At 2 to 3 ppm iron, even the genuine RFFE20-BB only lasts a few months for a family. A no-name cartridge with lower capacity exhausts even faster.
The Real Cost Comparison
No-Name Iron Cartridge
$80-150 + Unknown Capacity
❌Lifespan: Fails in 3-4 years
❌Result: Frequent repairs, poor water quality, leaks
❌Support: None
Generic media, axial flow, frequent replacement
Best Long-Term Value
Big Blue Iron Reduction Kit
$329 + $40-60/cartridge
✅Lifespan: Lasts 15+ years
✅Result: Done right the first time, peace of mind
✅Support: Lifetime USA Support
Genuine Pentek, radial flow, 80K gal capacity at 1 ppm
For $329 plus $40 to $60 per cartridge change (roughly every 9 months at 1 ppm iron), you get a genuine Pentair Pentek kit with real, tested capacity and a radial flow design that actually works. If your iron is higher than trace levels, the honest answer is a backwashing iron filter, and we will tell you that before you buy.
Why this kit
This kit pairs the genuine Pentair Pentek 150233 Big Blue housing with a genuine Pentek RFFE20-BB radial flow iron reduction cartridge, rated for 80,000 gallons at 1 ppm iron and certified to NSF/ANSI 42 for material safety. The radial flow design forces water through the media from the outside in, maximizing contact time and iron removal per pass.
More importantly, we are honest about its limits. If your water test shows iron above 1 ppm, or any red/ferric iron, we will tell you to buy a backwashing iron filter instead, even though it is a more expensive product for us to sell.
Contact Us
800-460-5810
We're here to help.
30-Day Money-Back Guarantee
Backed by 32 Years of Water Treatment Experience
The Policy: if the 20" Big Blue Iron Reduction Filter Kit doesn't meet your expectations within 30 days of purchase, contact us for a full refund. We ship a quality product from a trusted manufacturer and stand behind it completely.
32 YrsEXPERIENCE
10,000+SYSTEMS SOLD
4.8★Success Rate
After 32 years of helping homeowners fix their water, we know iron cartridges are one of the most over-sold products in this industry. Retailers push them for all iron problems because they are cheap and easy to ship. The reality is they only work for trace dissolved iron. We chose the genuine Pentair Pentek RFFE20-BB because it is honest, tested, and we know exactly where it works and where it does not.
The "Iron Cartridge for Everything" Trap
+
Generic retailers sell iron cartridges to anyone who mentions iron in their water, regardless of level or type. When the cartridge clogs in weeks because the iron is too high, or fails because the iron is ferric, the buyer blames the product instead of the recommendation. A cartridge iron filter is a real product for a specific, narrow use case. Outside that use case, it is throwing money away.
How Our Guarantee Works
1
It Doesn't Meet Your Expectations
If the kit arrives damaged, doesn't fit your plumbing, or doesn't do what you expected, contact us within 30 days.
2
We Make It Right
Call or text Aidan at 800-460-5810. We'll troubleshoot first, since many issues are simple installation fixes or water chemistry mismatches we can diagnose. If the cartridge is wrong for your water, we will credit you toward the right system.
Free Tech Support for Life
Every product we sell comes with free lifetime technical support. Not sure whether your iron level is low enough for a cartridge, or whether you need a backwashing tank? Call us. You'll talk to a real person who knows iron treatment, not a script reader.
I have helped homeowners with iron for over 30 years. Iron cartridges are a great fit for trace dissolved iron below about 1 ppm where a full backwashing filter is overkill. But they are not magic, and they are not for everyone. If you call me with your water test, I will tell you honestly which one you need.
