Marina 125 Cartridge

A 2-pack of replacement power cartridges for the Marina i25 internal aquarium filter

£6.49

· tracked · UK mainland estimate · 14-day promise

UK delivery £2.99 · free over £39

Secure checkout by Stripe · Card, Apple Pay & Klarna

On fit

This is specific to the Marina i25 internal filter and not a universal cartridge — check the model on your own filter before ordering, since a cartridge built for the wrong housing will not seat properly. No dimensions are given beyond that it is designed to fit inside the i25's own chamber.

Secure checkout

Tracked delivery

Easy returns

Easy to use, made to last

Why we chose it

Buying the two-pack means a spare is already in the cupboard for the next scheduled change, which is the difference between swapping a cartridge in seconds and running the tank on an exhausted one while a new one is on order. The 4-week replacement interval is Marina's own, not ours.

— Matt, founder

Specifications

Fits: Marina i25 internal filter (model A134)
Brand: Marina
Media: Zeolite, activated carbon, floss
Pack size: 2 cartridges
Replacement interval: 4 weeks

Full description

A filter cartridge does not announce when it stops working; the ammonia and odour it was trapping simply start building up again, which is why a fixed replacement schedule matters more than watching for cloudy water.

This is a replacement power cartridge for the Marina i25 internal filter, model code A134. Water is drawn through the centre of the cartridge first into a zeolite chamber that removes ammonia, then into an activated carbon chamber that takes out pollutants and odours, before passing through a floss layer that traps dirt and debris. Marina recommend replacing it every 4 weeks.

Replacement cartridge for the Marina i25 internal filter (model A134)
Two-chamber design: zeolite then activated carbon
Floss layer traps dirt and debris
Marina recommend replacing every 4 weeks
Pack contains 2 cartridges

On fit. This is specific to the Marina i25 internal filter and not a universal cartridge — check the model on your own filter before ordering, since a cartridge built for the wrong housing will not seat properly. No dimensions are given beyond that it is designed to fit inside the i25's own chamber.

Who it's for: Marina i25 filter owners working through their routine maintenance schedule, buying two cartridges at once rather than one at a time.

Delivery

Tracked UK delivery — your estimated arrival date is shown above and updates automatically. Standard delivery £2.99, and free on orders over £39. Full details on our delivery information page. Delivery information

Returns

14 days to change your mind, no interrogation. Items need to be unused (sensory products unopened, for hygiene). Full details on our delivery & returns page.

Payment

Secure checkout by Stripe — cards, Apple Pay, Link and Klarna. We never see or store your card details.

Common questions

What filter does this fit?

The Marina i25 internal filter, model code A134.

How many cartridges are in the pack?

Two.

How often should I replace it?

Marina recommend every 4 weeks.

What does the cartridge actually do?

It's a two-chamber design — zeolite removes ammonia, then activated carbon removes pollutants and odours — finished with a floss layer that traps dirt and debris.

What size is it?

2 cartridges. Every measurement we hold for this product is in the specifications above.

How long does delivery take?

Your estimated delivery date is shown above and updates automatically. UK orders are sent tracked — standard delivery is £2.99, and free on orders over £39.

How do I track my order?

As soon as your order is dispatched we email you a tracking link, so you can follow it all the way to your door.

What if I need to return my order?

You have 14 days from delivery to change your mind. Just email us with your order number and we’ll send the return steps the same working day — see our delivery & returns page for details.

Why buy from Giddy Pets?

Carefully selected by pet ownersEvery product is chosen and quality-checked by people who actually live with dogs, cats and small pets.
Tracked delivery on every orderUK delivery with tracking as standard — and it’s free when you spend over £39.
UK customer supportReal, UK-based humans read every email — usually Matt, the founder. No bots, no ticket numbers.
Easy returns14 days to change your mind, no interrogation. If it’s not right, we’ll make it right.