Aries FilterWorks AF-20-2125-BB 20" x 4.5" KDF-55 & Coconut Shell GAC Water Filter Cartridge - (2.5 lb) Reduces Chlorine, Heavy Metals, Scale & Microorganisms - Made in USA
Aries AF-20-2125-BB Filter Cartridge Details
| Dimensions | 20" length × 4.5" diameter |
| Filter Media | 2.5 lbs KDF-55 + coconut shell granular activated carbon |
| Micron Rating | 10 micron |
| Flow Rate | Up to 3 GPM (system-dependent) |
| Service Life | 6–12 months or 30,000–60,000 gallons |
| Operating Range | 40–100°F, 0–100 PSI |
| End Cap Style | Double-open-end (DOE) for tool-free installation |
| Manufacturing | Made in USA with FDA-approved materials |
Cartridge Replacement Procedure
- Shut off water supply and relieve pressure from the filter housing by opening a downstream faucet or pressing the housing's pressure relief button
- Unscrew the housing sump, remove the old cartridge, and clean the sump with warm water and mild detergent to remove sediment and biofilm
- Insert the new AF-20-2125-BB cartridge into the housing, ensuring the double-open-end design seats properly against both the cap and base
- Lubricate the housing o-ring with food-grade silicone grease, reassemble the housing, and slowly turn on water supply while checking for leaks
- Flush the cartridge for 5–10 minutes (10 times the bed volume) to remove carbon fines and activate the KDF-55 media before use
Housing and Application Fit
The Aries AF-20-2125-BB fits all standard 20-inch Full Flow (Big Blue) filter housings with 4.5" diameter capacity, including models from Pentek, GE, Culligan, Watts, Hydronix, and US Water Systems. The double-open-end construction works in both vertical and horizontal housing orientations. Ideal for whole house pre-filtration on municipal or well water, point-of-use drinking water systems, and upstream protection for reverse osmosis membranes or water softeners. The copper-zinc KDF-55 formulation provides bacteriostatic control in applications where microbial growth is a concern, while the coconut shell GAC addresses chloramines, chlorine, taste, odor, and organic compounds. Replace when pressure drop exceeds 15 PSI or at least annually, whichever comes first.
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Aries FilterWorks AF-20-2125-BB 20" x 4.5" KDF-55 & Coconut Shell GAC Water Filter Cartridge - (2.5 lb) Reduces Chlorine, Heavy Metals, Scale & Microorganisms - Made in USA
Aries FilterWorks AF-20-2125-BB 20" x 4.5" KDF-55 & Coconut Shell GAC Water Filter Cartridge - (2.5 lb) Reduces Chlorine, Heavy Metals, Scale & Microorganisms - Made in USA
Aries AF-20-2125-BB Filter Cartridge Details
| Dimensions | 20" length × 4.5" diameter |
| Filter Media | 2.5 lbs KDF-55 + coconut shell granular activated carbon |
| Micron Rating | 10 micron |
| Flow Rate | Up to 3 GPM (system-dependent) |
| Service Life | 6–12 months or 30,000–60,000 gallons |
| Operating Range | 40–100°F, 0–100 PSI |
| End Cap Style | Double-open-end (DOE) for tool-free installation |
| Manufacturing | Made in USA with FDA-approved materials |
Cartridge Replacement Procedure
- Shut off water supply and relieve pressure from the filter housing by opening a downstream faucet or pressing the housing's pressure relief button
- Unscrew the housing sump, remove the old cartridge, and clean the sump with warm water and mild detergent to remove sediment and biofilm
- Insert the new AF-20-2125-BB cartridge into the housing, ensuring the double-open-end design seats properly against both the cap and base
- Lubricate the housing o-ring with food-grade silicone grease, reassemble the housing, and slowly turn on water supply while checking for leaks
- Flush the cartridge for 5–10 minutes (10 times the bed volume) to remove carbon fines and activate the KDF-55 media before use
Housing and Application Fit
The Aries AF-20-2125-BB fits all standard 20-inch Full Flow (Big Blue) filter housings with 4.5" diameter capacity, including models from Pentek, GE, Culligan, Watts, Hydronix, and US Water Systems. The double-open-end construction works in both vertical and horizontal housing orientations. Ideal for whole house pre-filtration on municipal or well water, point-of-use drinking water systems, and upstream protection for reverse osmosis membranes or water softeners. The copper-zinc KDF-55 formulation provides bacteriostatic control in applications where microbial growth is a concern, while the coconut shell GAC addresses chloramines, chlorine, taste, odor, and organic compounds. Replace when pressure drop exceeds 15 PSI or at least annually, whichever comes first.
Original: $107.57
-65%$107.57
$37.65Product Information
Product Information
Shipping & Returns
Shipping & Returns
Description
Aries AF-20-2125-BB Filter Cartridge Details
| Dimensions | 20" length × 4.5" diameter |
| Filter Media | 2.5 lbs KDF-55 + coconut shell granular activated carbon |
| Micron Rating | 10 micron |
| Flow Rate | Up to 3 GPM (system-dependent) |
| Service Life | 6–12 months or 30,000–60,000 gallons |
| Operating Range | 40–100°F, 0–100 PSI |
| End Cap Style | Double-open-end (DOE) for tool-free installation |
| Manufacturing | Made in USA with FDA-approved materials |
Cartridge Replacement Procedure
- Shut off water supply and relieve pressure from the filter housing by opening a downstream faucet or pressing the housing's pressure relief button
- Unscrew the housing sump, remove the old cartridge, and clean the sump with warm water and mild detergent to remove sediment and biofilm
- Insert the new AF-20-2125-BB cartridge into the housing, ensuring the double-open-end design seats properly against both the cap and base
- Lubricate the housing o-ring with food-grade silicone grease, reassemble the housing, and slowly turn on water supply while checking for leaks
- Flush the cartridge for 5–10 minutes (10 times the bed volume) to remove carbon fines and activate the KDF-55 media before use
Housing and Application Fit
The Aries AF-20-2125-BB fits all standard 20-inch Full Flow (Big Blue) filter housings with 4.5" diameter capacity, including models from Pentek, GE, Culligan, Watts, Hydronix, and US Water Systems. The double-open-end construction works in both vertical and horizontal housing orientations. Ideal for whole house pre-filtration on municipal or well water, point-of-use drinking water systems, and upstream protection for reverse osmosis membranes or water softeners. The copper-zinc KDF-55 formulation provides bacteriostatic control in applications where microbial growth is a concern, while the coconut shell GAC addresses chloramines, chlorine, taste, odor, and organic compounds. Replace when pressure drop exceeds 15 PSI or at least annually, whichever comes first.












