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iSpring FC25BX4 20” x 4.5” Water Filter Replacement Cartridges, CTO Carbon Block, Fits Standard 20” x 4.5” Whole House Water Filter System, Pack of 4

Regular price $172.99
Sale price $172.99 Regular price $172.99
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iSpring FC25BX4
$172.99

Features

carbon water filters
  • Our FC25B CTO Carbon Block filters have a capacity of 100,000 gallons of water, enough to supply a family of four with clean water for a full year.

  • The FC25B carbon block filters are made of coconut shell carbon and are specially designed to remove up to 99% of chlorine from water as well as various other contaminants that cause unpleasant odors and tastes.

  • Why iSpring?

    At iSpring, we provide our customers with professional water solutions to any water concerns you may have.

  • Clean Water For the Ones You Love

    Save on your water bill - the filters won’t produce any wastewater.

    The filters are specially designed for a water flow: up to 15 gallons per minute.

    Unlike an RO membrane, the filters don’t reduce Total Dissolved Solids (TDS). If you are interested in a filter that removes TDS, consider our iSpring Reverse Osmosis (RO) systems.

Product Features

Size:4.5" x 20"

Usually used as the second stage for 20 in. whole house filters. The carbon block filter is manufactured using a continuous extrusion process. It consists of Activated Carbon. It is effective in reducing free chlorine, bad taste, odor, hazardous chemicals, and pesticides. Depending on the inlet water quality or flow rate, it needs to be replaced every 6 - 12 months or 100,000 Gal. of water.

  • AvailabilityIn Stock
  • Model FC25BX4
  • Manufacturer iSpring
  • Product Dimensions 20.0"L x 10.0"W x 10.0"H
  • Product Weight 24.0 LB

iSpring vs Other Brands

Feature
NSF/ANSI 58 Certification
Yes (full system certified)
Often partial or none
Verified performance & safety
Filtration Stages
Clear 3/4/5/7 stage options
Usually 4-5 stages
More complete options
Alkaline Remineralization
Available (RCC7AK/RCC7AK-UV)
Rare or expensive add-on
Better taste & pH balance
See-through 1st Stage Housing
Yes, smart flow sensor
Unavailable in most systems
Easy visual inspection
Daily Production
75 GPD (reliable output)
Often lower or overstated
Reliable daily production
Replacement Filters
Widely available & affordable
Hard or harder to find
Lower long-term cost
Installation
DIY friendly, no plumber needed
Can be more complex
Faster & easier set-up
Support & Warranty
Responsive support + solid warranty
Varies widely
Better post-purchase experience
Value for Money
High performance at competitive price
Higher price for similar specs
Better cost-effectiveness

Reviews

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How to install