Top 10 CTO Carbon Filter – Replacement Under-Sink Water Filters
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Peace of mind customer service: register online to activate your manufacturer and life-time free tech support from U. They are tested by an independent third-party to meet NSF/ANSI standards. 5” housings, including brand name models.
The 20” x 4. 5” filter cartridges have a minimum impact on water flow up to 15 GPM and require minimum maintenance. Top-notch quality: our fc25b cto carbon block filters are made of high-quality coconut shell activated carbon for maximum filtration efficiency and filter life. S. Activated carbon is an effective adsorbent because it is a highly porous material and provides a large surface area to which contaminants may adsorb.


Fits other standard 10" x 4. 5"big blue undersink and whole house water filtration systems. No leaching carbon ash. Usually used as the second stage filter for whole house water filtration systems, FC15B brings clean and refreshing water to every faucet in your home.
Steady flow and high absorption. Great compatibility official replacement filter for ispring under sink water filter system US21B and Whole House water filtration systemsWGB21B, WGB21BM, and WGB21B-PB. Exceptional filtration performance knocks out cloudiness as well as bad tastes and odors, removes up to 99% of chlorine, and is highly effective on Organic Compounds like herbicides, and industrial solvents and other contaminants like trihalomethanes. Replace the filter every 6 months or every 50, 000 gallons of water for optimal performance.

100% money-back guaranteesix-months return policy guaranteed! product life time warranty on every filter confirmed with defects in material and Workmanship and Any Filter Caused Malfunction Within Each Filter’s Service Life. High capacity the cto carbon filter can filter up to 13000 gallons depending on water quality.
5 inch filter models of dupont wfpfc8002, pentek cbc-10, 46942, ecolab 9320-1002, flotec to1, ace hardware 84608, dupont dwc30001, whirlpool whcf-whwc, cornelius cor10b1, everpure cg5-10, wfdwc30001, ge fxwtc, cor10b5, GE FX12P, WFPFC8002, Apex IR-40, wfpfc9001, Aquaboon CTO, Culligan D-10A & D-10, pfc8002, DEV9108-15, wfpfc9001, SCWH-5, GXWH20F. If your water source is well water, BPA FREE Certified. Our ro carbon filter is made of 100% pure coconut shell activated carbon block to remove most sediments, Sintering Technology ensures high absorbing capacity offers a much finer filtration of suspended particles and dirt.

Your easy and smart coconut shell carbon filter. Universal 10-inch replacement – elegantly designed at 2. 5” x 10”, it will fit all standard 10 inch Reverse Osmosis and Under Sink Systems. Have a piece of mind knowing your water is purified with the superior Aquaboon filtration system.
Aquaboon – your smartest coconut shell water filter solution! Lifetime - 6 month Replace once or twice times a year, depending on the water quality.

100% safe: our replacement water filter cartridge is verified by independent laboratory tests, compliance with NSF 42 certification standards to ensure your safe. Easy installation: universal 10 inch cartridge, fits most standard under-sink RO system, whole house 10” standard filter housing and any 10” water filtration unit.
Excellent customer service: we provide one year warranty and 30 days money back, do not hesitate to contact us, if you have any questions, lifetime friendly customer service, we will always to stand help you. Outer layer has food grade plastic net wrapping PP non-woven fabric, which can last up to six months. Drop-in designed for easy and quick filter change, no tools required.

Universal 10-inch replacement – elegantly designed at 2. 5” x 10”, it will fit all standard 10 inch Reverse Osmosis and Under Sink Systems. Aquaboon – your smartest coconut shell water filter solution! Lifetime - 6 month Replace once or twice times a year, so you can trust it won’t go to waste, depending on the water quality.
Have a piece of mind knowing your water is purified with the superior Aquaboon filtration system. Enjoy long-lasting coconut shell activated carbon water filters. Your easy and smart coconut shell carbon filter. Long lasting – your carbon block activated water filter comes in an airtight packaging, works better and lasts longer.

Well-fit following housings: pentek bbfs-222, water filters depot wfd h-20bb-1pr, h-h201bbe, geekpure bb-20b, hfpp-1-pr20, 150235 and 150233, h2o splash whbb20t1bl, Premier Water Systems WF45-20-1NPT, aquaboon ab-wh20bb, Hydronix HX-HF45-20BLBK10, ispring hb28bx2 and wgb12b, simpure rswhb002z_s8, Max Water B078FPN68M.


Completely clean water make your home contamination-free by removing chlorine and other harmful industrial chemicals - Now you can drink water knowing it is 100% safe. Universal 10-inch replacement – elegantly designed at 2. 5” x 10”, it will fit all standard 10 inch Reverse Osmosis and Under Sink Systems.
Your easy and smart coconut shell carbon filter. Aquaboon – your smartest coconut shell water filter solution! Lifetime - 6 month Replace once or twice times a year, depending on the water quality. Long lasting – your carbon block activated water filter comes in an airtight packaging, so you can trust it won’t go to waste, works better and lasts longer.
1. iSpring
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Grey, 4.5" x 20", iSpring FC25B High Capacity 20” x 4.5” Water Filter Replacement Cartridge Whole House Big Blue CTO Carbon Block
#adiSpring #ad - If you are interested in a filter that removes TDS, the filters don’t reduce Total Dissolved Solids TDS, consider our iSpring Reverse Osmosis RO systems. Unlike an ro membrane, and instead keeps healthy minerals in your water. Please unwrap the cartridges before use.Peace of mind customer service: register online to activate your manufacturer and life-time free tech support from U. They are tested by an independent third-party to meet NSF/ANSI standards. 5” housings, including brand name models.
More information #ad
Local support team. We are happy to help! Please note: the cartridges are individually wrapped to ensure freshness. We stand behind our products and if you encounter any problems with any of our products please reach out to us immediately. The 20” x 4. 5” filter cartridges have a minimum impact on water flow up to 15 GPM and require minimum maintenance. Top-notch quality: our fc25b cto carbon block filters are made of high-quality coconut shell activated carbon for maximum filtration efficiency and filter life. S. Activated carbon is an effective adsorbent because it is a highly porous material and provides a large surface area to which contaminants may adsorb.
Brand | iSpring #ad |
Manufacturer | iSpring #ad |
Height | 20 Inches |
Length | 4.5 Inches |
Weight | 5.2 Pounds |
Width | 4.5 Inches |
Part Number | FC25B |
Model | FC25B |
More information #ad
2. iSpring
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White, 9-3/4" x 2-7/8", 5 Microns, iSpring FC15 FC15-10 CTO Carbon Block Filter Cartridge
#adiSpring #ad - Nominal filtration rating of 5 microns. Reduces fine sediment and chlorine taste and odor in residential and commercial Drinking water. Bonded pac media with polyolefin pre-filter and polyethylene netting for extended life.More information #ad
Initial pressure drop of 3. 4 psi at a flow rate of 1 gpm. Water temperature range of 40 to 180 degrees F 4. 4 to 82. 2 degrees C.Brand | iSpring #ad |
Manufacturer | iSpring Water Systems #ad |
Height | 10 Inches |
Length | 2.5 Inches |
Width | 2.5 Inches |
Part Number | FC15 |
Model | FC15 |
More information #ad
3. iSpring
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Big Blue 5-Micron 10"x4.5", iSpring FC15B High Capacity Activated CTO Carbon Block Filter Replacement Cartridge for Under Sink and Whole House Water Filtration System, 4.5"x4.5"x10"
#adiSpring #ad - Premium quality material using high-quality coconut shell carbon and highly compact fabrication tech, this highly activated carbon block CTOChlorine, binders, Taste, and Odor filter cartridge is designed and produced to achieve maximum filtration efficiency and filter life for 10" Under Sink Water Filter and Whole House Water Filtration Systems.Fits other standard 10" x 4. 5"big blue undersink and whole house water filtration systems. No leaching carbon ash. Usually used as the second stage filter for whole house water filtration systems, FC15B brings clean and refreshing water to every faucet in your home.
More information #ad
Individually sealed for freshness. Long filter life filters up to 50, 000 gallons depending on the use and feed water quality. Free of surfactants, and adhesives. Peace-of-mind customer support your risk-free shopping experience is backed by a 30-day money-back guarantee and lifetime tech support from iSpring in Atlanta, GA. Steady flow and high absorption. Great compatibility official replacement filter for ispring under sink water filter system US21B and Whole House water filtration systemsWGB21B, WGB21BM, and WGB21B-PB. Exceptional filtration performance knocks out cloudiness as well as bad tastes and odors, removes up to 99% of chlorine, and is highly effective on Organic Compounds like herbicides, and industrial solvents and other contaminants like trihalomethanes. Replace the filter every 6 months or every 50, 000 gallons of water for optimal performance.
Brand | iSpring #ad |
Manufacturer | iSpring Water Systems #ad |
Height | 10 Inches |
Length | 4.5 Inches |
Weight | 0.9 Pounds |
Width | 4.5 Inches |
Part Number | FC15B |
Model | FC15B |
Warranty | 30-Day Money Back Guarantee and Extended Warranty upon Registration. Lifetime CS and tech support from Atlanta, GA. |
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4. PUREPLUS
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4Pack, WHCF-WHWC, 1 Micron 2.5" x 10" Whole House CTO Carbon Water Filter Cartridge Replacement for Countertop Water Filter System, WFPFC9001, WHEF-WHWC, AMZN-SCWH-5, Dupont WFPFC8002, FXWTC, SCWH-5
#adPUREPLUS #ad - The filter reduces up to 99% of chlorine, sediment, Australia Water Mark, color, this filter may not achieve the filtering effect you expect. This kind of filter is recommended for tap water filtration. Higher quality filtration carbon is well known for its unique absorbing ability, a pound of carbon is able to provide up 125 acres of filtering surface area.100% money-back guaranteesix-months return policy guaranteed! product life time warranty on every filter confirmed with defects in material and Workmanship and Any Filter Caused Malfunction Within Each Filter’s Service Life. High capacity the cto carbon filter can filter up to 13000 gallons depending on water quality.
More information #ad
Let it bring a wonderful cleaner water experience to your loved ones. Suggest to replace it every 3- 6 months for the average household for optimal performance depending on the use. Compatible filters the filter can be used in any standard 10” x2. 5” ro unit whole house filtration system and compatible with standard 10 inch x 2. 5 inch filter models of dupont wfpfc8002, pentek cbc-10, 46942, ecolab 9320-1002, flotec to1, ace hardware 84608, dupont dwc30001, whirlpool whcf-whwc, cornelius cor10b1, everpure cg5-10, wfdwc30001, ge fxwtc, cor10b5, GE FX12P, WFPFC8002, Apex IR-40, wfpfc9001, Aquaboon CTO, Culligan D-10A & D-10, pfc8002, DEV9108-15, wfpfc9001, SCWH-5, GXWH20F. If your water source is well water, BPA FREE Certified. Our ro carbon filter is made of 100% pure coconut shell activated carbon block to remove most sediments, Sintering Technology ensures high absorbing capacity offers a much finer filtration of suspended particles and dirt.
Brand | PUREPLUS #ad |
Manufacturer | PUREPLUS #ad |
Part Number | 43222-1615 |
Warranty | ❄️We offer 3-Month Return Policy Assurance! ❄️Within 30 days counted from the date of purchase, you are free to request return directly from Amazon. ❄️After 30 days return window but within 6-month counted from the date of purchase, you are still eligible to initiate a return request by simply contacting us. |
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5. Aquaboon
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Aquaboon Coconut Shell Water Filter Cartridge | Activated Carbon Block CTO | Universal 5 Micron 10 inch Cartridge | Compatible with DWC30001, WHKF-WHWC 4-Pack, WHEF-WHWC, FXWTC, WFPFC8002
#adAquaboon #ad - Long lasting – your carbon block activated water filter comes in an airtight packaging, so you can trust it won’t go to waste, works better and lasts longer. Enjoy long-lasting coconut shell activated carbon water filters. Ultra-high grade filtration – our pure water coconut carbon filter is extensively tested and verified to meet health and product standards.Your easy and smart coconut shell carbon filter. Universal 10-inch replacement – elegantly designed at 2. 5” x 10”, it will fit all standard 10 inch Reverse Osmosis and Under Sink Systems. Have a piece of mind knowing your water is purified with the superior Aquaboon filtration system.
More information #ad
Completely clean water make your home contamination-free by removing chlorine and other harmful industrial chemicals - Now you can drink water knowing it is 100% safe. Compatible replacement filters ace hardware 84608, wfpfc9001, pure-tel w5cip, wfpfc8002, to1-ss24-05, optipure w-5, cor10b5, c1, ecolab 9320-1002, dev9108-15, cto-10, pfc8002, to1-s, 46942, to1-ss24-02, to1-ds, watts f109009, to1-ss, to1-ss24-01, wfdwc30001, gxwh20f, fxwtc, Dupont DWC30001, omnifilter to1, to1-d, ge fx12p, whirlpool whef-whwc, Apex IR-40, everpure cg5-10, pentair dev9108-15, whkf-whwc, nucalgon 4711-87, TO-1, sears 34370, flotec to1, cornelius cor10b1, to1ds, fltr-2112, etc. Aquaboon – your smartest coconut shell water filter solution! Lifetime - 6 month Replace once or twice times a year, depending on the water quality.
Brand | Aquaboon #ad |
Manufacturer | Aquaboon #ad |
Height | 9.75 Inches |
Weight | 4 Pounds |
Part Number | B01LZAQWXT |
More information #ad
6. SimPure
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4 Pack, 5 Micron 10" x 2.5" Carbon Block Filter Cartridge Replacement, Whole House CTO Carbon Sediment Water Purifier Filter Compatible with Most RO System, SimPure Carbon Water Filter
#adSimPure #ad - Food grade efficiency filtration: designed with 10” x 2. 5” slim carbon block filter, organic chemicals and odor, filters up to 15, effectively removes 97% sediment, 000 gallons, filtration rating is 5 micron, chlorine, etc. Durable and sealed end caps with sealed silicon O-ring prevent leak.100% safe: our replacement water filter cartridge is verified by independent laboratory tests, compliance with NSF 42 certification standards to ensure your safe. Easy installation: universal 10 inch cartridge, fits most standard under-sink RO system, whole house 10” standard filter housing and any 10” water filtration unit.
More information #ad
Provide quite clean and fresh water for your family. High quality materials: simpure activated carbon filter is made of high quality coconut shell carbon. Excellent customer service: we provide one year warranty and 30 days money back, do not hesitate to contact us, if you have any questions, lifetime friendly customer service, we will always to stand help you. Outer layer has food grade plastic net wrapping PP non-woven fabric, which can last up to six months. Drop-in designed for easy and quick filter change, no tools required.
Brand | SimPure #ad |
Manufacturer | SimPure #ad |
Part Number | RSCTO001Z_4S8 |
Model | 1025 |
More information #ad
7. Aquaboon
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Aquaboon Coconut Shell Water Filter Cartridge | Activated Carbon Block CTO | Universal 5 Micron 10 inch Cartridge | Compatible with DWC30001, WHKF-WHWC 3-Pack, WHEF-WHWC, FXWTC, WFPFC8002
#adAquaboon #ad - Ultra-high grade filtration – our pure water coconut carbon filter is extensively tested and verified to meet health and product standards. Completely clean water make your home contamination-free by removing chlorine and other harmful industrial chemicals - Now you can drink water knowing it is 100% safe.Universal 10-inch replacement – elegantly designed at 2. 5” x 10”, it will fit all standard 10 inch Reverse Osmosis and Under Sink Systems. Aquaboon – your smartest coconut shell water filter solution! Lifetime - 6 month Replace once or twice times a year, so you can trust it won’t go to waste, depending on the water quality.
More information #ad
Compatible replacement filters ace hardware 84608, wfpfc8002, to1-d, fxwtc, dupont dwc30001, watts f109009, to-1, nucalgon 4711-87, flotec to1, c1, pure-tel w5cip, ecolab 9320-1002, 46942, cor10b5, everpure cg5-10, pfc8002, cto-10, dev9108-15, optipure w-5, pentair dev9108-15, cornelius cor10b1, TO1-S, fltr-2112, ge fx12p, WFPFC9001, sears 34370, gXWH20F, to1-ss24-05, apex ir-40, whirlpool whef-whwc, omnifilter to1, whkf-whwc, to1-ss24-02, WFDWC30001, TO1-SS24-01, to1-ss, to1-ds, to1ds, etc. Have a piece of mind knowing your water is purified with the superior Aquaboon filtration system. Enjoy long-lasting coconut shell activated carbon water filters. Your easy and smart coconut shell carbon filter. Long lasting – your carbon block activated water filter comes in an airtight packaging, works better and lasts longer.
Brand | Aquaboon #ad |
Manufacturer | Aquaboon #ad |
Height | 9.75 Inches |
Weight | 3 Pounds |
Part Number | B01LY00V99 |
More information #ad
8. Ronaqua
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FC25B, FLTWH2045C02 and PRL-RCL, 4pcs Big Blue CTO Carbon Block Water Filters 4.5" x 20" Whole House Cartridges Set WELL-MATCHED with CB-45-2005
#adRonaqua #ad - Dimensions: 20 inches x 4. 5 inches 508 cm x 11. 43 cm. Product lifetime - 20, 000 gallons - replace two or three times a year - depending on your water quality. Universal replacement for all 20" big blue water filter housingand and well-matched models of cartridges: pelican water prl-rcl, pentek 155783-43, cb-bb-20, pentek ep20-bb, CB-45-2010, pelican cb-bb-20, watts WCBCFF20, EPM-20BB, BC20-BB-5, CBC-20BB, Hydronix CB-45-2005, ispring fc25b, FLTWH2045C02.More information #ad
Keeps water fresh by reducing and removing iron, pesticides, herbicides, manganese, chlorine, hydrogen sulfide, and other industrial chemicals. This filter is wrapped and sealed and meets nsf national Science Foundation Standards and Regulations. Well-fit following housings: pentek bbfs-222, water filters depot wfd h-20bb-1pr, h-h201bbe, geekpure bb-20b, hfpp-1-pr20, 150235 and 150233, h2o splash whbb20t1bl, Premier Water Systems WF45-20-1NPT, aquaboon ab-wh20bb, Hydronix HX-HF45-20BLBK10, ispring hb28bx2 and wgb12b, simpure rswhb002z_s8, Max Water B078FPN68M.
Brand | Ronaqua #ad |
Manufacturer | Ronaqua #ad |
Height | 20 Inches |
Length | 20 Inches |
Width | 4.5 Inches |
Part Number | 4C-20BB |
More information #ad
9. iSpring
#ad
ISpring F3 6-Month Prefilter Replacement Supply Filter Cartridge Pack Set for Standard Reverse Osmosis RO Systems, F3
#adiSpring #ad - 5" replacement water filters included: 1x sediment filters, 1x granular activated carbon filters, and 1x carbon block filters. This filter pack does NOT include an RO membrane. Experience clean, safe, and good-tasting water every time you turn on the faucet.More information #ad
If you have trouble installing the filters, please refer to the user manual or contact us. 3 pieces of 10" x 2. Individually wrapped 6-month high capacity prefilter replacement cartridge pack for most standard RO filtration systems.Brand | iSpring #ad |
Manufacturer | iSpring #ad |
Height | 3 Inches |
Length | 10 Inches |
Weight | 4 Pounds |
Width | 3 Inches |
Part Number | F3 |
Model | F3 |
More information #ad
10. Aquaboon
#ad
WHKF-WHWC 2-Pack, WFPFC8002, FXWTC, Aquaboon Coconut Shell Water Filter Cartridge | Activated Carbon Block CTO | Universal 5 Micron 10 inch Cartridge | Compatible with DWC30001, WHEF-WHWC
#adAquaboon #ad - Have a piece of mind knowing your water is purified with the superior Aquaboon filtration system. Enjoy long-lasting coconut shell activated carbon water filters. Ultra-high grade filtration – our pure water coconut carbon filter is extensively tested and verified to meet health and product standards.Completely clean water make your home contamination-free by removing chlorine and other harmful industrial chemicals - Now you can drink water knowing it is 100% safe. Universal 10-inch replacement – elegantly designed at 2. 5” x 10”, it will fit all standard 10 inch Reverse Osmosis and Under Sink Systems.
More information #ad
Compatible replacement filters ace hardware 84608, apex ir-40, to1ds, everpure cg5-10, 46942, to1-ds, to1-s, to-1, optipure w-5, to1-ss24-01, to1-ss24-02, ecolab 9320-1002, cornelius cor10b1, fltr-2112, whirlpool whef-whwc, to1-ss, wfpfc9001, nucalgon 4711-87, flotec to1, pentair DEV9108-15, omnifilter to1, whkf-whwc, Dupont DWC30001, ge fx12p, pfc8002, watts f109009, fxwtc, dev9108-15, wfpfc8002, Pure-Tel W5CIP, to1-ss24-05, Sears 34370, cto-10, COR10B5, gxwh20f, TO1-D, wfdwc30001, c1, etc. Your easy and smart coconut shell carbon filter. Aquaboon – your smartest coconut shell water filter solution! Lifetime - 6 month Replace once or twice times a year, depending on the water quality. Long lasting – your carbon block activated water filter comes in an airtight packaging, so you can trust it won’t go to waste, works better and lasts longer.
Brand | Aquaboon #ad |
Manufacturer | Aquaboon #ad |
Height | 9.75 Inches |
Weight | 2 Pounds |
Part Number | B01LZAQYNU |
More information #ad