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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

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(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
Auto Ship
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
Auto Ship
(2 Pack) Smart Pack Water Filters IF2-CB8 (CB8) Carbon Block Water Filter Compatible with Amway E-84, E-85, A101, E-9225- 2 Pack
Smart Pack

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

IF2-CB8
in stock

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

Upgrade your drinking water with the Smart Pack QC2-CB8 2-Pack Carbon Block Water Filters, a premium replacement for Amway E-84, E-85, A101, and E-...

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$75.99 - $75.99
$75.99
$75.99 - $75.99
$75.99
Auto Ship
(2 Pack) Smart Pack Water Filters IF2-HDG-CB-6-14 CB6 Carbon Block Water Filter Replacement, MP MPC Systems
(2 Pack) Smart Pack Water Filters IF2-HDG-CB-6-14 CB6 Carbon Block Water Filter Replacement, MP MPC Systems
Smart Pack

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

IF2-HDG-CB-6-14
in stock

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

Deliver fresh, better-tasting water to your home with the Smart Pack QC-CB6 2-Pack Carbon Block Replacement Filters, made for Multipure Aquaversa a...

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$57.00 - $57.00
$57.00
$57.00 - $57.00
$57.00
Auto Ship
iFilters Smart Pack Water Filters IF-CB6 (CB6) Carbon Block Water Filter Replacement, MP MPC Systems
iFilters Smart Pack Water Filters IF-CB6 (CB6) Carbon Block Water Filter Replacement, MP MPC Systems
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Smart Pack

Smart Pack 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 Smart Pack QC-CB6 Carbon Block Water Filter Replacement, designed for Multipure Aquaversa...

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$37.99
$37.99 - $37.99
$37.99
$34.99
$34.99 - $34.99
$34.99
Sale Sale
Auto Ship
RP-3500 Replacement Water Filter, 1000 Gal, Compatible with Frescapure 3500 WF0451 - IFilters
RP-3500 Variations
iFilters

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
Auto Ship
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
Auto Ship
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
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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
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2 Pack Compatible Fit Frescapure 4000 4500 5000 6000 Water Filter Replacement
Smart Pack

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

RP-CB456505/2
in stock

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

Enjoy cleaner, better-tasting water with the Smart Pack Royal Prestige Carbon Block Replacement Filter 2-Pack. Designed for FrescaPure 4000, 4500, ...

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$99.99 - $99.99
$99.99
$99.99 - $99.99
$99.99
Auto Ship
2 Pack RP-3500 Replacement Water Filter, Compatible with Frescapure 3500 WF0451 - IFilters
RP-3500 Variations
iFilters

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

RP-3500/2
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 to the WF0451 filter used in the RP 5300 water filtration systems. Made from c...

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$109.99 - $109.99
$109.99
$109.99 - $109.99
$109.99
Auto Ship
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
Auto Ship
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
Auto Ship
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
Auto Ship
Smart Pack Water Filters CB8 Carbon Block Water Filter Compatible with Amway E-84, E-85, A101, E-9225
Smart Pack

Smart Pack 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 Smart Pack CB8 Carbon Block Water Filter, a reliable replacement for Amway E‑84, E‑85, A101, E‑9225...

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$43.07 - $43.07
$43.07
$43.07 - $43.07
$43.07
Auto Ship
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
Auto Ship
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
Auto Ship
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
Auto Ship
Smart Pack Water Filters High Purity Coconut Shell Activated Carbon Water Filter - 750 GPD Life Span - 0.5 Micron - Compatible with Frescapure 4000 4500 5000 6000 Models
RP-CB456505 Variations
Smart Pack

Smart Pack 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 Smart Pack Royal Prestige Carbon Block Replacement Filter. Designed for FrescaPure 4000, 4500, 5000, 6...

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$55.00 - $55.00
$55.00
$55.00 - $55.00
$55.00
Auto Ship
Alkaline PH Drinking Water Filter for Chlorine, Chloramines, Taste, Odor, Heavy Metals - IFilters
Alkaline PH Drinking Water Filter for Chlorine, Chloramines, Taste, Odor, Heavy Metals - IFilters
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
Auto Ship
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
Auto Ship
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
Auto Ship
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
Auto Ship
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
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