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Carbon CTO

Clean drinking water starts with the right filter. Our Carbon CTO replacement filters are designed to improve taste, reduce odors, and target common contaminants found in municipal and well water. These carbon block cartridges use compressed activated carbon to trap chlorine, sediment, and other unwanted particles. Many models also support cyst and lead reduction when paired with compatible systems. With multiple sizes and micron ratings available, you can match the right filter to your existing housing or reverse osmosis setup.

About Our CTO Carbon Block Filtration Cartridges

Carbon block filtration products are known for their dense structure and consistent performance. Unlike loose granular carbon, a solid carbon block forces water through tightly packed media for better contact time. This design helps reduce chlorine taste and odor while supporting cleaner, clearer water at every tap. Our selection includes coconut shell carbon options, standard 2.5 x 10 cartridges, whole house sizes, and compatible replacements for popular systems. You can also choose multi-pack options for convenient scheduled changes throughout the year.

Why Choose iFilters for Carbon CTO Products?

At iFilters, we focus on offering dependable replacement filters that fit a wide range of residential and light commercial systems. Our inventory includes trusted brands and compatible alternatives, so you can shop with confidence. Detailed product listings make it easy to confirm dimensions, micron ratings, and compatibility before you buy. Many Carbon CTO options are available with Auto Ship, helping you stay on schedule without last-minute orders. We also keep popular items in stock, so your water system stays running without unnecessary downtime.

Shop Carbon CTO online today!

Filters

(2 Pack) Genuine Hydro Guard HDG-CB6-14/2 - CB6 Carbon Block Water Filter For MP Systems
HDG-CB-6-14 Variations
Hydro Guard

(2 Pack) Genuine Hydro Guard HDG-CB6-14/2 - CB6 Carbon Block Water Filter For MP Systems

HDG-CB6-14/2
in stock

$64.99 - $64.99
$64.99
$64.99 - $64.99
$64.99

(2 Pack) Genuine Hydro Guard HDG-CB6-14 Carbon Block Water Filter – Compatible with MP Systems Only looking for 1 filter? Order here: HDG-CB6-14 Th...

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$64.99 - $64.99
$64.99
$64.99 - $64.99
$64.99
iFilters CBSM-2510 Coconut Shell CTO, Carbon Block Drinking Water Filter, 2.5 x 10, 0.5 Micron - IFilters
iFilters CBSM-2510 Coconut Shell CTO Carbon Block Drinking Water Filter – 2.5" x 10", 0.5 Micron
iFilters

iFilters CBSM-2510 Coconut Shell CTO, Carbon Block Drinking Water Filter, 2.5 x 10, 0.5 Micron

CBSM-2510
in stock

$19.99 - $19.99
$19.99
$19.99 - $19.99
$19.99

iFilters CBSM-2510 Coconut Shell CTO Carbon Block Drinking Water Filter – 2.5" x 10", 0.5 Micron High-Performance Filtration for Clean, Great-Tasti...

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$19.99 - $19.99
$19.99
$19.99 - $19.99
$19.99
iFilters Compatibles

iFilters Compatibles IF2-CB8 Replacement Water Filter – 0.5 Micron Carbon Block for Amway E-84, E-85, A101 & E-9225 2 Pack

IF-CB8-2PK
in stock

$75.99 - $75.99
$75.99
$75.99 - $75.99
$75.99

Upgrade your drinking water with the iFilters Compatibles QC2-CB8 2-Pack Carbon Block Water Filters, a premium replacement for Amway E-84, E-85, A1...

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$75.99 - $75.99
$75.99
$75.99 - $75.99
$75.99
iFilters Compatibles

iFilters Compatibles CB6 2-Pack 0.5-Micron Carbon Block Under-Sink Water Filter Replacement | Multipure Aquaversa Compatible – 2.5″ x 6.5″

IF-CB6-2PK
in stock

$57.00 - $57.00
$57.00
$57.00 - $57.00
$57.00

Deliver fresh, better-tasting water to your home with the iFilters Compatibles IF-CB6-2PK 2-Pack Carbon Block Replacement Filters, made for Multipu...

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$57.00 - $57.00
$57.00
$57.00 - $57.00
$57.00
Sale Sale
iFilters Compatibles

iFilters Compatibles CB6 Compatible Carbon Block Water Filter Replacement – 0.5 Micron Under-Sink Cartridge for Multipure Aquaversa Systems

IF-CB6
in stock

$37.99
$37.99 - $37.99
$37.99
$34.99
$34.99 - $34.99
$34.99

Keep your drinking water clean, clear, and tasty with the iFilters Compatibles QC-CB6 Carbon Block Water Filter Replacement, designed for Multipure...

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$37.99
$37.99 - $37.99
$37.99
$34.99
$34.99 - $34.99
$34.99
Sale Sale
iFilters Compatibles

RP-3500 Replacement Water Filter, 1000 Gal, Compatible with Frescapure 3500 WF0451

RP-3500
in stock

$59.95 - $59.95
$59.95
$59.95 - $59.95
$59.95

iFilters RP-3500 is a 100% compatible alternative replacement to the WF0451 filter used in the RP 3500 water filtration systems. Made from certifie...

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$59.95 - $59.95
$59.95
$59.95 - $59.95
$59.95
2 PK Carbon Block Drinking Water Filter Replacement for Lead Asbestos CTO
Hydronix

2 PK Carbon Block Drinking Water Filter Replacement for Lead Asbestos CTO

SMCB-2510/2
in stock

$23.00 - $23.00
$23.00
$23.00 - $23.00
$23.00

Hydronix SMCB-2510 carbon block filters are NSF/ANSI standard 42 certified for Material and structural Safety. SMCB-2520 filters have a particle re...

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$23.00 - $23.00
$23.00
$23.00 - $23.00
$23.00
Hydro Guard HDG-CB6-14 (CB6) Carbon Block Water Filter Replacement Cartridge NSF-certified
Hydro Guard HDG-CB6-14 (CB6) Carbon Block Water Filter Replacement Cartridge NSF-certified
Hydro Guard

Hydro Guard HDG-CB6-14 (CB6) Carbon Block Water Filter Replacement Cartridge NSF-certified

HDG-CB6-14
in stock

$35.99 - $35.99
$35.99
$35.99 - $35.99
$35.99

Hydro Guard HDG-CB6-14 Carbon Block Water Filter – CB6 Compatible Replacement Cartridge (NSF) The Hydro Guard HDG-CB6-14 Carbon Block Water Filter ...

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$35.99 - $35.99
$35.99
$35.99 - $35.99
$35.99
Hydronix CB-25-1005 Whole House RO Drinking Water Coconut Carbon Block Water Filter 5 m 2.5" x 10"
Hydronix CB-25-1005 Whole House RO Drinking Water Coconut Carbon Block Water Filter 5 m 2.5" x 10"
Hydronix

Hydronix CB-25-1005 Whole House RO Drinking Water Coconut Carbon Block Water Filter 5 m 2.5" x 10"

CB-25-1005
in stock
$10.99 - $10.99
$10.99
$10.99 - $10.99
$10.99

Hydronix CB-25-1005 Whole House RO Coconut Carbon Block Water Filter – 5 Micron, 2.5" x 10" Premium Carbon Block Filtration for Cleaner, Better-Tas...

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$10.99 - $10.99
$10.99
$10.99 - $10.99
$10.99
iFilters Compatibles

iFilters Compatibles Royal Prestige Replacement Filter – 0.5 Micron Coconut Shell Carbon Block Under-Sink Water Filter 2-Pack

RP-CB456505-2PK
in stock

$99.99 - $99.99
$99.99
$99.99 - $99.99
$99.99

Enjoy cleaner, better-tasting water with the iFilters Compatibles Royal Prestige Carbon Block Replacement Filter 2-Pack. Designed for FrescaPure 40...

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$99.99 - $99.99
$99.99
$99.99 - $99.99
$99.99
iFilters Compatibles

2 Pack RP-3500 Replacement Water Filter, Compatible with Frescapure 3500 WF0451

RP-3500-2PK
in stock
$109.99 - $109.99
$109.99
$109.99 - $109.99
$109.99

2 Pack iFilters RP-3500 is a 100% compatible alternative replacement for the WF0451 filter used in the RP 5300 water filtration systems. Made from ...

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$109.99 - $109.99
$109.99
$109.99 - $109.99
$109.99
Hydro Guard HDG-CB-8-38 (CB8), Amway E84, A101, E-9225 Compatible Carbon Block Water Filter
Hydro Guard

Hydro Guard HDG-CB-8-38 (CB8), Amway E84, A101, E-9225 Compatible Carbon Block Water Filter

HDG-CB-8-38
in stock

$35.84 - $35.84
$35.84
$35.84 - $35.84
$35.84

Hydro Guard HDG-CB8-38 Carbon Block Water Filter – Compatible with CB8, Amway E84, A101, & E-9225 The Hydro Guard HDG-CB8-38 Carbon Block Water...

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$35.84 - $35.84
$35.84
$35.84 - $35.84
$35.84
Coconut Shell CTO, Carbon Block Water Filter Cartridge, 0.5 Micron 2.5 x 10
Hydronix

Coconut Shell CTO, Carbon Block Water Filter Cartridge, 0.5 Micron 2.5 x 10

SMCB-2510
in stock

$14.00 - $14.00
$14.00
$14.00 - $14.00
$14.00

Hydronix SMCB-2510 carbon block filters are NSF/ANSI standard 42 certified for Material and structural Safety. SMCB-2520 filters have a particle re...

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$14.00 - $14.00
$14.00
$14.00 - $14.00
$14.00
4 Pk Carbon Block Water Filter CTO Whole House RO DI Hydroponics 5 μm 10" x 2.5" - IFilters
4 Pk Carbon Block Water Filter CTO Whole House RO DI Hydroponics 5 μm 10" x 2.5" - IFilters
Hydronix

4 Pk Carbon Block Water Filter CTO Whole House RO DI Hydroponics 5 μm 10" x 2.5"

CB-25-1005/4
in stock
$34.99 - $34.99
$34.99
$34.99 - $34.99
$34.99

4 Pack - Hydronix Carbon Block Filters are manufactured with high purity coconut shell carbon. These Coconut Carbon Block filters provide an excell...

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$34.99 - $34.99
$34.99
$34.99 - $34.99
$34.99
iFilters Compatibles

iFilters Compatibles CB8 Replacement Filter – 0.5 Micron Carbon Block Under‑Sink Water Filter

IF-CB8
in stock

$43.07 - $43.07
$43.07
$43.07 - $43.07
$43.07

Enjoy fresher, cleaner water every day with the iFilters Compatibles CB8 Carbon Block Water Filter, a reliable replacement for Amway E‑84, E‑85, A1...

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$43.07 - $43.07
$43.07
$43.07 - $43.07
$43.07
2 Pack Whole House RO Drinking Systems Coconut Carbon Water Filter 5 μm 2.5 x 10
2 Pack Whole House RO Drinking Systems Coconut Carbon Water Filter 5 μm 2.5 x 10
Hydronix

2 Pack Whole House RO Drinking Systems Coconut Carbon Water Filter 5 μm 2.5 x 10

CB-25-1005/2
in stock
$17.27 - $17.27
$17.27
$17.27 - $17.27
$17.27

Hydronix CB-25-1005 Carbon Block filters are NSF/ANSI Standard 42 certified for material and structural safety. CB-25-1005 filters have a particle ...

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$17.27 - $17.27
$17.27
$17.27 - $17.27
$17.27
Hydro Guard HDG-CB6-38 Carbon Block Water Filter Replacement, 3/8" NPT Port
Hydro Guard

Hydro Guard HDG-CB6-38 Carbon Block Water Filter Replacement, 3/8" NPT Port

HDG-CB6-38
in stock

$36.99 - $36.99
$36.99
$36.99 - $36.99
$36.99

Hydro Guard HDG-CB6-38 Carbon Block Water Filter – 0.5 Micron, 3/8" NPT Port The Hydro Guard HDG-CB6-38 Carbon Block Water Filter delivers premium ...

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$36.99 - $36.99
$36.99
$36.99 - $36.99
$36.99
Whole House & RO Coconut Activated Carbon Block Water Filter 5 μm 2.5" x 20"
Hydronix

Whole House & RO Coconut Activated Carbon Block Water Filter 5 μm 2.5" x 20"

CB-25-2005
in stock
$18.51 - $18.51
$18.51
$18.51 - $18.51
$18.51

Hydronix CB-25-2005 carbon block filters are NSF/ANSI standard 42 certified for Material and structural Safety. CB-25-2005 filters have a particle ...

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$18.51 - $18.51
$18.51
$18.51 - $18.51
$18.51
iFilters Compatibles

iFilters Compatibles Royal Prestige Replacement Filter – 0.5 Micron Coconut Shell Carbon Block Under-Sink Water Filter

RP-CB456505
in stock

$55.00 - $55.00
$55.00
$55.00 - $55.00
$55.00

Enjoy cleaner, better-tasting water with the iFilters Compatibles Royal Prestige Carbon Block Replacement Filter. Designed for FrescaPure 4000, 450...

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$55.00 - $55.00
$55.00
$55.00 - $55.00
$55.00
PRO+AQUA

Alkaline PH Drinking Water Filter for Chlorine, Chloramines, Taste, Odor, Heavy Metals

FC-10-ALK
in stock
$40.99 - $40.99
$40.99
$40.99 - $40.99
$40.99

Convert any standard water filtration unit into an Alkaline Drinking Water System with the PRO+AQUA FC-10-ALK Multi-Stage Alkaline Drinking Water F...

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$40.99 - $40.99
$40.99
$40.99 - $40.99
$40.99
Coconut Shell CTO, Carbon Block Water Filter Cartridge, 0.5 Micron 2.5 x 20 - IFilters
Coconut Shell CTO, Carbon Block Water Filter Cartridge, 0.5 Micron 2.5 x 20 - IFilters
Hydronix

Coconut Shell CTO, Carbon Block Water Filter Cartridge, 0.5 Micron 2.5 x 20

SMCB-2520
in stock

$23.74 - $23.74
$23.74
$23.74 - $23.74
$23.74

Hydronix SMCB-2520 carbon block filters are NSF/ANSI standard 42 certified for Material and structural Safety. SMCB-2520 filters have a particle re...

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$23.74 - $23.74
$23.74
$23.74 - $23.74
$23.74
4 PK - Coconut Shell CTO Carbon Block Water Filter for Whole house & RO 1 Micron - IFilters
Hydronix

4 PK - Coconut Shell CTO Carbon Block Water Filter for Whole house & RO 1 Micron

CB-25-1001/4
in stock
$29.74 - $29.74
$29.74
$29.74 - $29.74
$29.74

The Hydronix CB-25-1001 NSF Certified Carbon Block water filter is manufactured with high purity coconut shell carbon and is available in a wide ra...

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$29.74 - $29.74
$29.74
$29.74 - $29.74
$29.74
Hydronix CB-25-0505 NSF Coconut Activated Carbon Block Water Filter 5 μm 2.5 x 5
Hydronix

Hydronix CB-25-0505 NSF Coconut Activated Carbon Block Water Filter 5 μm 2.5 x 5

CB-25-0505
in stock

$6.90 - $6.90
$6.90
$6.90 - $6.90
$6.90

The Hydronix CB-25-0505 NSF Certified Carbon Block water filter is manufactured with high purity coconut shell carbon and is available in a wide ra...

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$6.90 - $6.90
$6.90
$6.90 - $6.90
$6.90
Arsenic & Chlorine Carbon Block Water Filter Cartridge, 5 micron 2.5 x 10 - IFilters
Hydronix

Arsenic & Chlorine Carbon Block Water Filter Cartridge, 5 micron 2.5 x 10

CB-AR-2510
in stock

$27.99 - $27.99
$27.99
$27.99 - $27.99
$27.99

The Hydronix CB-AR-2510 Arsenic filter has a particle retention Size of 5 microns, and are ideal for drinking water filtration applications. The Hy...

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$27.99 - $27.99
$27.99
$27.99 - $27.99
$27.99
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