What happens if I don't change it?

Spent carbon stops removing odours and discolouration, and clogged pads slow the flow, so the filter moves less water through the tank.

Aquarium filter media

Aqua One Sponge 35ppi 138s (25138S) for Ocellaris 850 and Ocellaris 850UVC

25138S

Fits 2 models

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GenuineGenuine Aqua One

$8.94 each

2-pack $17.88

Aquarium Spare Parts · 30 OctLowest genuine · Aquarium Spare Parts · checked 30 Oct

CompatibleCompatible option

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Genuine: made by Aqua One. Compatible: another brand.Genuine is made by Aqua One. Compatible is made by another brand. Check the seller's page for the size and models it fits.

Lowest price · $8.94 each · 2-pack $17.88

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Open Aquarium Spare Parts · $8.94 each · 2-pack $17.88

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Genuine Aqua One

1 seller

Aquarium Spare PartsGenuine · checked 30 OctGenuine part · Lowest genuinechecked 30 Oct$8.94 each2-pack $17.88OpenGo to seller

Open cheapest seller · $8.94 each · 2-pack $17.88

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How long it lasts

Replace it when it clogs, breaks down or no longer holds its shape, Aqua One says; until then rinse it in a bucket of aquarium water each time you clean the filter.

How to change the 25138S aquarium filter media

Watch the guide or follow the steps.

Aqua One Ocellaris 850/1400 Canister Filter · Aqua One (official)

1Turn the canister filter off at the power point and unplug it. Close the taps or flow valve and disconnect the tap connector from the head unit (Nautilus: lift the locking lever).
2Fill a bucket with water from your aquarium. Release the clips, lift off the head unit and take the media baskets out of the canister.
3Take out the sponges and the white wool. Dunk the baskets of biological media a few times in the bucket of aquarium water: Aqua One says this keeps the chlorine in tap water from killing the good bacteria on it.
4Rinse the sponges in the bucket of aquarium water. Fit a new fine sponge (35ppi) once the old one clogs and water no longer passes through it easily.
5Put the media back in the same baskets and order, refit the baskets and head unit, then prime and restart the filter as its manual describes.

Every number this part goes by138S · 25138S

Retail name:: 138S
Retail name:: 25138S

Sellers list any of these; they are the same part.

Will it fit your appliance?

Type your model number and we'll check it against the makers' lists.

Your appliance model

Fits these 2 Aqua One modelsOcellaris 850, Ocellaris 850UVC

Aqua One2 models

Fine 35ppi sponge sold on its own (also in the media set).

Common questionsWhat does the 25138S fit? · Where can I buy the 25138S in Australia? · How do I fit the 25138S?

What does the 25138S fit?: The Aqua One Sponge 35ppi 138s (25138S) for Ocellaris 850 and Ocellaris 850UVC fits the Aqua One Ocellaris 850 and Ocellaris 850UVC.
Where can I buy the 25138S in Australia?: We track 1 Australian seller for the 25138S; the lowest listed price when we last checked was A$8.94 at Aquarium Spare Parts. Prices are re-checked daily and dated on this page.
How do I fit the 25138S?: No tools, a few minutes: 5 steps, listed on this page with the replacement video where the maker has one.
What happens if I don't change it?: Spent carbon stops removing odours and discolouration, and clogged pads slow the flow, so the filter moves less water through the tank.

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