

Hero image 0 of iSpring Whole House Water Filter Cartridge, Carbon Water Filter, 20” x 4.5”, Model: FC25B, 0 of 4
iSpring Whole House Water Filter Cartridge, Carbon Water Filter, 20” x 4.5”, Model: FC25B
Key item features
- High-Quality Carbon: Made from high-quality coconut shell carbon and individually wrapped for freshness. Tested by independent third-party to meet NSF/ANSI Standard.
- Effective Filtration: Reduces sediment, chlorine, and removes unpleasant odors and tastes, ensuring clean water.
- Standard Size: Fits 20" Big Blue Water Filter Housings, typically used in whole house filter systems.
- Temperature and Pressure: Operates effectively with source water temperatures between 40F ~ 125F and a pressure impact of 5 psi drop at a flow rate of 5 gpm.
- Chlorine Removal: Designed to remove up to 99% of chlorine, along with various organic compounds, taste and odor compounds, and synthetic chemicals.
- Durable Construction: Manufactured using a continuous extrusion process, ensuring lower pressure drop, no release of carbon fines, and high physical strength.
- Long-Lasting: Needs replacement every 6 months or 100,000 gallons of water, depending on inlet water quality or flow rate.
- Minimal Maintenance: The 20 x 4.5 filter cartridges have a minimal impact on water flow (up to 15 GPM) and require minimal maintenance.
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Specs
- BrandiSpring
- Rec. useResidential
- Assembled product height20 in
- Color categoryWhite
Current price is USD$51.49
Price when purchased online
- Free shipping
Free 30-day returns
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Arrives by Wed, Jun 17
|Sold and shipped by iSpring Water Systems, LLC
4.63063063063063 stars out of 5, based on 222 seller reviews(4.6)222 seller reviews
Free 30-day returns
About this item
Product details
Usually used as the second stage for 20 in. Big Blue whole house filters. The carbon block filter is manufactured using a continuous extrusion process. It consists of a high quality virgin premium performance Activated Carbon. It is effective in reducing free chlorine, bad taste, odor THM, Organics, hazardous chemicals, and pesticides. Depending on the inlet water quality or flow rate, it needs to be replaced every 6 months or 100,000 Gal. of water.Individually wrapped for freshnessLower pressure drop, no release of carbon fines, great physical strength, highly porous, high adsorption, steady flow, highly uniform, and solid structure integrityLength: 20 in., O.D. = 4.5 in., I.D.= 1 in.1/4 in. fitting
- Made from high-quality coconut shell carbon and individually wrapped for freshness. Tested by independent third-party to meet NSF/ANSI Standard
- Effective reduction of sediment, chlorine, and a high removal capacity of unpleasant odors, and tastes
- 4.5" (Dia) x 20" (Length) fits 20" Big Blue Water Filter Housings usually in whole house filter
- Source water temperature 40°F ~ 125°F. Pressure impact: 5 psi drop at a flow rate of 5 gpm
- Free tech support from Atlanta (678) 261-7611
-
- Protect Your Family and Household Appliance from Chlorine and More: Say goodbye to smelly, bad tasting water! The FC25B carbon block filter is specially designed to remove up to 99% of chlorine from water as well as various natural organic compounds, taste and odor compounds, and synthetic organic chemicals.
- Standard Size: Our filter set fits standard 20” x 4. 5” housings, including brand name models.
- 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. Activated carbon is an effective adsorbent because it is a highly porous material and provides a large surface area to which contaminants may adsorb. They are tested by an independent third-party to meet NSF/ANSI standards. The 20” x 4. 5” filter cartridges have a minimum impact on water flow (up to 15 GPM) and require minimum maintenance
- Peace of Mind Customer Service: Register online to activate your manufacturer and life-time free tech support from U. S. local support team. We stand behind our products and if you encounter any problems with any of our products please reach out to us immediately. We are happy to help!
- Please Note: The cartridges are individually wrapped to ensure freshness. Please unwrap the cartridges before use. Unlike an RO membrane, the filters don’t reduce Total Dissolved Solids (TDS), and instead keeps healthy minerals in your water. If you are interested in a filter that removes TDS, consider our iSpring Reverse Osmosis (RO) systems.
- Protect Your Family and Household Appliance from Chlorine and More: Say goodbye to smelly, bad tasting water! The FC25B carbon block filter is specially designed to remove up to 99% of chlorine from water as well as various natural organic compounds, taste and odor compounds, and synthetic organic chemicals.
- Standard Size: Our filter set fits standard 20” x 4. 5” housings, including brand name models.
- 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. Activated carbon is an effective adsorbent because it is a highly porous material and provides a large surface area to which contaminants may adsorb. They are tested by an independent third-party to meet NSF/ANSI standards. The 20” x 4. 5” filter cartridges have a minimum impact on water flow (up to 15 GPM) and require minimum maintenance
- Peace of Mind Customer Service: Register online to activate your manufacturer and life-time free tech support from U. S. local support team. We stand behind our products and if you encounter any problems with any of our products please reach out to us immediately. We are happy to help!
- Please Note: The cartridges are individually wrapped to ensure freshness. Please unwrap the cartridges before use. Unlike an RO membrane, the filters don’t reduce Total Dissolved Solids (TDS), and instead keeps healthy minerals in your water. If you are interested in a filter that removes TDS, consider our iSpring Reverse Osmosis (RO) systems.
info:
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Specifications
Brand
iSpring
Rec. use
Residential
Assembled product height
20 in
Housing material
coconut shell activated carbon
Warranty
Warranty information
Please be aware that the warranty terms on items offered for sale by third party Marketplace sellers may differ from those displayed in this section (if any). To confirm warranty terms on an item offered for sale by a third party Marketplace seller, please use the 'Contact seller' feature on the third party Marketplace seller's information page and request the item's warranty terms prior to purchase.
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Showing 1-2 of 2 reviews
Sep 9, 2025
Lat 26˚
5 out of 5 stars review
Seller Verified Purchase
Chemical Manufacturer
I manufacturer cleaning products for the marine industry. As such I need the best water to mix my products. The filters provided have fulfilled that need by removing all the contaminates.
Review from iSpring Water Systems
Helpful?6ID4R9OGSM83188988751
Aug 1, 2024
James
5 out of 5 stars review
I purchased the 3-stage whole house filtration system 3 years ago. After the initial installation I searched for less expensive filter cartridges. I was very disappointed in the cheaper versions and have since changed back to the iSpring CTO cartridges. They are constructed much better and last 4 times longer than the cheaper brands I tried. I have learned my lesson. I highly recommend the iSpring CTO cartridges!
Review from iSpring Water Systems
Helpful?6ID4R9OGSM83188988751
