Trevoli GAC20B 20" Jumbo Granular Activated Carbon Filter - 25 Micron NZ

Trevoli GAC20B — 20" Jumbo Granular Activated Carbon Filter

Reduce chlorine, taste, and odour from your water supply — 20" Jumbo size.

The Trevoli GAC20B is a 20" x 4.5" Jumbo granular activated carbon cartridge for taste, chlorine, and odour reduction. Made from premium quality coconut shell activated carbon, it is often used for reverse osmosis pre-filtration and a wide range of whole-house filtration applications.

The 20" length holds more carbon media than the 10" GAC10B — providing a longer service life and extended contact time with the water between replacements. A better choice for larger households, higher-usage installations, or where longer service intervals are preferred.

Granular activated carbon (GAC) contains loose carbon granules — less dense than a carbon block filter, which gives it a higher flow rate but a slightly lower contact time with the water. Polypropylene sediment filtration pads at each end keep the carbon granules contained and provide additional coarse filtration.

This cartridge is replace-only — it is not cleanable or reusable. Replace every 6–12 months or sooner if taste or odour returns.

Fits most 20" Jumbo (Big Blue or Big White) housings — including Pentair, Puretec, Davey, and most other major brands. Jumbo housings take a 4.5" diameter cartridge.

Key Specs at a Glance

• Media: Granular activated carbon (coconut shell)
• Micron rating: 25 micron
• Size: 20" x 4.5" (Jumbo)
• Cleanable and reusable: No — replace only
• Replace: Every 6–12 months, or when taste or odour returns
• Certifications: None
• Fits: Most 20" Jumbo (Big Blue / Big White) housings

Frequently Asked Questions

What does this cartridge treat?

Granular activated carbon reduces taste, odour, and chlorine in your water supply. It is not a sediment filter — for sediment removal, a pleated or polyspun cartridge should be installed upstream.

What is the difference between the GAC10B and GAC20B?

Both use the same coconut shell carbon media at 25 micron. The GAC20B is longer — it holds more carbon media, which extends service life and provides more contact time between the water and the carbon. Choose the 20" if you have a larger household, higher usage, or want longer intervals between cartridge changes.

What is the difference between GAC and a carbon block?

GAC contains loose carbon granules and is less dense than a carbon block. This gives it a higher flow rate but slightly lower contact time with the water. Carbon block filters are denser and offer more thorough treatment — but at a lower flow rate. GAC is a good choice where flow is a priority.

Can I clean and reuse this cartridge?

No. Carbon cartridges are replace-only — the carbon media is consumed during use and cannot be regenerated or cleaned. Replace every 6–12 months or when taste or odour returns.

Will it fit my housing?

This cartridge fits most 20" Jumbo housings — the key measurement is diameter. Jumbo housings take a 4.5" diameter cartridge. If your housing takes a 2.5" diameter cartridge, you need the Standard size, not this one.

Is there a KDF version available?

Yes — the 20KDF-GAC combines granular activated carbon with KDF media for additional reduction of heavy metals, iron, and hydrogen sulfide. Note: the KDF version is suitable for chlorinated mains water only.

What warranty applies?

Filter cartridges are consumable items. If you receive a cartridge that appears damaged or defective on arrival, get in touch and we'll sort it out.