Fluval Tri Ex Absorbing Cartridge G6
Suits tanks
Up to 600 L
Flow rate
1000 L/h
Water type
Freshwater
Fits
Fluval G6 canister filter
Part no.
A424
Fluval Tri Ex Absorbing Cartridge G6
Handles three jobs in one cartridge slot on the Fluval G6. The Tri-EX cartridge combines activated carbon with phosphate- and nitrate-removing resin in a single unit, sized for the chemical media stage of the Fluval G6 canister filter (Fluval item A424). It tackles odour, discolouration and the two nutrients that drive algae growth in one pass, without needing three separate media baskets.
Will it fit my filter?
Yes, if you run a Fluval G6 canister filter. The G6 is rated for aquariums up to 600 L (160 US gal), with a maximum flow around 1,000 L/h (264 US GPH). This cartridge is sized for the G6's media basket only — it does not fit the smaller Fluval G3, which takes its own Tri-EX cartridge (item A423).
Key features
- Three media in one cartridge — activated carbon, phosphate-removing resin and nitrate-removing resin combined, so you're not running separate baskets for each.
- Purpose-built for the G6 — shaped to seat correctly in the G6's chemical stage, unlike generic universal carbon pads.
- Targets the causes of algae flare-ups — phosphate and nitrate removal addresses the nutrients that feed nuisance algae, not just the symptoms.
- Drop-in replacement — swaps in during a normal filter service, no cutting or repacking required.
Specifications
| Field | Details |
|---|---|
| Fits | Fluval G6 canister filter only — not compatible with the smaller Fluval G3, which uses its own Tri-EX cartridge (item A423) |
| Manufacturer part number | A424 |
| Media type | Activated carbon, phosphate-removing resin and nitrate-removing resin combined in one 3-in-1 cartridge |
| Removes / provides | Phosphate, nitrate, organic waste, odour and discolouration |
| Water type | Freshwater |
| Replacement interval | Not published by Fluval — check water clarity and nitrate/phosphate test results every 4 to 6 weeks, and replace once readings stop improving after a water change |
Suitable for, and not suitable for
Suitable for freshwater aquariums running a Fluval G6. Not recommended for reef or invertebrate systems, where phosphate stripping needs to be more gradual and controllable — a dedicated reactor is the better tool there. It's not a substitute for the G6's separate mechanical and biological media, which still need their own regular servicing.
Care and maintenance
Fluval does not publish a fixed replacement interval for this cartridge. As a general guide, check water clarity and your nitrate/phosphate test results every 4 to 6 weeks, and replace the cartridge once readings stop improving after a water change.
Warranty and delivery
This is a consumable filter media, used until exhausted rather than covered under a mechanical warranty. Standard parcel delivery.
Common questions
Can I use this in a Fluval G3 instead of a G6?
No. The G3 takes its own Tri-EX cartridge, item A423, sized for its smaller housing. The two aren't interchangeable.
Do I need a separate carbon cartridge as well?
No. This cartridge already includes activated carbon alongside the phosphate and nitrate resin, so a separate carbon cartridge isn't needed at the same time.
Will this affect phosphate dosing on a reef tank?
This cartridge is intended for freshwater use. On a reef tank, faster or less predictable phosphate stripping can undo deliberate dosing — a controllable reactor media is the better choice there.
