The Fluval AquaClear 20 takes the Fluval BIOMAX for AC20/AC30 Power Filter, 42 g (part 19660) as its biological media; Australian sellers list it from A$8.88 as of 30 October 2026. Fitment confirmed against the manufacturer's compatibility list.
Your aquarium filter
Fluval AquaClear 20
Aquarium filter
Confirmed against Fluval's listConfirmed against Fluval's own compatibility list
Not yours? Change
Takes the 19660 biological media
BIOMAX for AC20/AC30 Power Filter, 42 g · check the code printed on your old filter before ordering.
Your aquarium filter
Aquarium filter
Confirmed against Fluval's listConfirmed against Fluval's own compatibility list
Takes the 19660
Biological media · check the code on your old filter.
Other Fluval aquarium filters that take the 19660
GenuineGenuine Fluval
$8.88
Aquarium Spare Parts · 30 OctLowest genuine · Aquarium Spare Parts · checked 30 Oct
CompatibleCompatible option
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Genuine: made by Fluval. Compatible: another brand.Genuine is made by Fluval. Compatible is made by another brand. Check the seller's page for the size and models it fits.
Lowest price · $8.88
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Other parts this aquarium filter takes
- Fluval Carbon for AC20/AC30 Power Filter, 50 gOpen Aquarium Spare Parts$4.63 each · 3-pack $13.88
The carbon filter. Separate from the biological media. Reduces odours, discolouration and dissolved impurities (carbon). Replace every month.
- Fluval Intake Strainer Sponge for AC20/AC30/AC50 Power FilterOpen Aquarium Spare Parts$6.88
The intake sponge. Separate from the biological media. Reduces debris at the intake.
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AUD, before delivery. Each price shows when it was checked.
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How long it lasts
Replace it as needed: Fluval gives no set interval for this BIOMAX, and says never to rinse it in tap water or replace all the media at once.
How to change the biological media in your Fluval AquaClear 20
Watch the guide or follow the steps.
- 1Unplug the filter.
- 2Lift the media basket out of the filter body.
- 3Rinse foam in water from the aquarium; rinse BIOMAX in aquarium water only: Fluval says never to rinse it with tap water.
- 4Fit the new BIOMAX in its compartment. Fluval says not to replace all filter media at the same time, so the bacteria on the other media carry on.
- 5Put the media basket back in the filter and plug it in.
Every number this part goes by
- Retail name:
- 19660
Sellers list any of these; they are the same part.
About your Fluval AquaClear 20
Fluval aquarium filter — AquaClear power filter (hang-on). Its biological media is the BIOMAX for AC20/AC30 Power Filter, 42 g, part 19660.
Also in this aquarium filter: Fluval Carbon for AC20/AC30 Power Filter, 50 g (every month), Fluval Intake Strainer Sponge for AC20/AC30/AC50 Power Filter.
Where the model number is: The model is on the filter's lid, motor head or a label on its side (Fluval 307, Eheim Classic 2215). For a tank with a built-in filter, use the tank's name.
Fits these 2 Fluval models
Fluval2 models
Common questions
- Which biological media fits the Fluval AquaClear 20?
- The Fluval AquaClear 20 takes the Fluval BIOMAX for AC20/AC30 Power Filter, 42 g (part 19660).
- Where can I buy the 19660 in Australia?
- We track 1 Australian seller for the 19660; the lowest listed price when we last checked was A$8.88 at Aquarium Spare Parts. Prices are re-checked daily and dated on this page.
- How do I fit the 19660 in a Fluval AquaClear 20?
- 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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