20" Jumbo KDF/GAC Water Filter Cartridge

Improve water quality with a 20" Jumbo KDF/GAC water filter cartridge that combines granular activated coconut shell carbon with KDF media in one cartridge.

The GAC media helps reduce chlorine, unpleasant taste and odour, while the KDF media works alongside the carbon to support cartridge performance.

Choose Value Waimana for straightforward KDF/GAC filtration with polypropylene sediment filtration pads at each end, or Premium Pentair Pentek for high-performance granular activated coconut shell carbon, KDF media designed to inhibit scale buildup, and a dedicated 5 micron spun-bonded polypropylene post-filter.

Both cartridges measure 20" × 4½" and are designed for compatible 20" Jumbo / Big Blue water filter housings.

Product Options

Value — Waimana 20GAC/KDF

The Waimana 20GAC/KDF combines KDF media with premium-quality coconut shell granular activated carbon in a 20" × 4½" Jumbo cartridge, rated at 5 micron.

The activated carbon helps reduce chlorine, unpleasant taste and odour, while the KDF media helps prolong the life and increase the effectiveness of the carbon filtration media.

The cartridge also incorporates polypropylene sediment filtration pads at each end, providing additional sediment filtration around the KDF/GAC media.

Choose Value for dependable everyday KDF/GAC filtration in a larger 20" Jumbo format.

Premium — Pentair Pentek 20BKDF-GAC

The Pentair Pentek 20BKDF-GAC is a premium 20" × 4½" KDF/GAC purifier cartridge designed for high-capacity chlorine, taste and odour reduction.

The cartridge combines high-performance granular activated coconut shell carbon with KDF media designed to inhibit scale buildup within the filter that can decrease cartridge life.

It also incorporates a 5 micron spun-bonded polypropylene post-sediment element, providing additional sediment filtration and increased dirt-holding capacity.

Choose Premium where you want high-performance carbon media, scale-control functionality and dedicated 5 micron post-filtration in a 20" Jumbo cartridge.

Why Choose This Water Filter Cartridge?

• KDF + GAC filtration — combines two treatment media within one cartridge.
• Chlorine reduction — both options help reduce chlorine from the water.
• Taste and odour improvement — coconut shell activated carbon helps treat common taste and odour issues.
• 20" × 4½" Jumbo format — both options are designed for compatible 20" Jumbo / Big Blue housings.
• Coconut shell activated carbon — used for effective carbon treatment.
• Sediment filtration included — Waimana uses polypropylene filtration pads, while Pentair incorporates a dedicated 5 micron post-filter.
• Two treatment levels — choose Value for straightforward KDF/GAC filtration or Premium for additional scale-control and post-filtration features.
• Premium scale control — Pentair's KDF media helps inhibit scale buildup within the cartridge.
• Premium 5 micron post-filtration — provides additional sediment filtration and increased dirt-holding capacity.
• 20" cartridge format — provides a larger filtration cartridge for compatible 20" Jumbo systems.

How It Works

A KDF/GAC cartridge combines KDF media with GAC — Granular Activated Carbon.

As water travels through the cartridge, the granular activated coconut shell carbon provides adsorption treatment for chlorine, unpleasant taste and odour.

The KDF media works alongside the carbon.

In the Waimana 20GAC/KDF, KDF helps prolong the life and increase the effectiveness of the carbon filtration media.

In the Pentair 20BKDF-GAC, KDF media is designed to inhibit scale buildup within the cartridge, helping prevent scale accumulation from decreasing cartridge life.

The Pentair cartridge also incorporates a 5 micron spun-bonded polypropylene post-filter, adding sediment filtration after the KDF/GAC treatment media.

Best Suited For

This 20" Jumbo KDF/GAC water filter cartridge is well suited to:

• Mains-water filtration
• Chlorine reduction
• Taste and odour treatment
• Residential water filtration
• Whole-house filtration systems
• 20" Jumbo / Big Blue filter housings
• Multi-stage water filtration systems
• Applications requiring KDF and GAC in one cartridge
• Reverse-osmosis prefiltration where compatible
• General water-quality improvement
• Higher-capacity filtration applications

The Premium Pentair is particularly useful where lime and scale buildup within the filter is a concern.

Key Specifications

Value vs Premium — Which Should I Choose?

Choose Value Waimana if you want:

• KDF/GAC filtration
• Coconut shell activated carbon
• Chlorine reduction
• Taste and odour improvement
• Polypropylene sediment filtration pads
• KDF to help prolong carbon life
• KDF to increase carbon effectiveness
• 20" × 4½" Jumbo sizing
• A practical, cost-effective replacement option

For straightforward filtration, the Waimana 20GAC/KDF provides the core benefits of KDF and granular activated carbon in a 20" Jumbo cartridge.

Choose Premium Pentair if you want:

• High-performance granular activated coconut shell carbon
• KDF media designed to inhibit scale buildup
• 5 micron post-sediment filtration
• Increased dirt-holding capacity
• High-capacity chlorine taste and odour reduction
• 20" × 4½" Jumbo sizing
• Better suitability where lime and scale buildup within the filter is a concern
• A premium Pentair Pentek cartridge

The main reason to choose Premium is its combination of high-performance GAC, scale-control functionality and dedicated 5 micron post-filtration.

GAC vs Carbon Block — What's the Difference?

These cartridges use GAC — Granular Activated Carbon rather than a solid carbon block.

GAC contains loose activated carbon granules and is less dense than compressed carbon-block media.

This construction allows the cartridge to combine granular coconut shell carbon with KDF media within the same treatment cartridge.

If your priority is chlorine, taste and odour treatment combined with the additional benefits of KDF media, a KDF/GAC cartridge is a practical option.

Installation

This cartridge is designed for use in a compatible 20" Jumbo / Big Blue water filter housing.

Both Value and Premium options measure 20" × 4½".

To replace the cartridge:

1. Turn off the water supply.
2. Release pressure from the filter housing.
3. Remove the filter housing sump.
4. Remove the existing cartridge.
5. Clean the housing if required.
6. Check that the O-ring is clean and seated correctly.
7. Insert the new KDF/GAC cartridge.
8. Reassemble the housing.
9. Slowly restore water pressure.
10. Check the housing carefully for leaks.
11. Flush the new cartridge before normal use.

Maintenance

Cartridge life depends on:

• Incoming water quality
• Water usage
• Chlorine levels
• Sediment loading
• Scale conditions
• System flow

Replace the cartridge when chlorine taste or odour begins to return, treatment performance noticeably declines, or water flow becomes excessively restricted.

What's Included

1 × 20" Jumbo KDF/GAC Water Filter Cartridge

Choose from:

Value — Waimana Water 20GAC/KDF

or

Premium — Pentair Pentek 20BKDF-GAC

Both options measure 20" × 4½".

Frequently Asked Questions

What does a KDF/GAC water filter do?

A KDF/GAC cartridge combines granular activated carbon with KDF media.

The activated carbon reduces chlorine and improves unpleasant taste and odour, while the KDF media works alongside the carbon to support cartridge performance.

What does GAC mean?

GAC stands for Granular Activated Carbon.

Unlike a compressed carbon block, GAC consists of loose activated carbon granules.

What does the KDF do?

In the Waimana 20GAC/KDF, KDF helps prolong carbon life and increase the effectiveness of the carbon media.

In the Pentair 20BKDF-GAC, the KDF media is designed to inhibit scale buildup within the filter.

Does it reduce chlorine?

Yes. Both options are designed to reduce chlorine.

Does it help with taste and odour?

Yes. The granular activated coconut shell carbon helps reduce unpleasant taste and odour.

What's the difference between Value and Premium?

The Value Waimana 20GAC/KDF combines KDF, coconut shell activated carbon and polypropylene sediment filtration pads.

The Premium Pentair 20BKDF-GAC combines high-performance granular activated coconut shell carbon with KDF media designed to inhibit scale buildup, plus a dedicated 5 micron spun-bonded polypropylene post-filter.

Does the Waimana filter sediment?

Yes. The Waimana cartridge incorporates polypropylene sediment filtration pads at each end.

Does the Pentair filter sediment?

Yes. The Pentair incorporates a 5 micron spun-bonded polypropylene post-sediment element, providing additional sediment filtration and increased dirt-holding capacity.

Which option should I choose for scale-prone water?

Choose the Premium Pentair 20BKDF-GAC where lime and scale buildup within the cartridge is a concern.

Its KDF media is designed to inhibit scale buildup that can otherwise decrease cartridge life.

Is this a carbon block filter?

No. These cartridges use granular activated carbon (GAC) rather than compressed carbon block media.

Are both cartridges the same size?

Yes. Both the Waimana 20GAC/KDF and Pentair 20BKDF-GAC measure 20" × 4½".

Will this fit my 20" Jumbo housing?

Both options are designed for compatible 20" Jumbo / Big Blue water filter housings.

The cartridge dimensions are 20" × 4½".

What's the difference between a 10" and 20" KDF/GAC cartridge?

The main physical difference is cartridge length.

This listing is specifically for 20" × 4½" Jumbo cartridges and requires a compatible 20" Jumbo housing. A 10" cartridge is designed for a shorter 10" housing.