Saddleback anemonefish (Amphiprion polymnus) care guide

Group
Marine fish
Other names
Yellowfin anemonefish, Saddleback clownfish
Family
Pomacentridae (damselfishes and clownfishes)
Origin
Philippines, Indonesia and New Guinea to northern Australia, Melanesia and the Ryukyu Islands; silty lagoons and harbours at 2–30 m.
Water
saltwater
Maximum size
13 cm
Temperature
24–27°C
pH
8.1–8.4
Hardness
Salinity SG 1.023–1.026
Minimum tank
90 litres
Care level
intermediate
Temperament
semi_aggressive
Reef safe
yes

Care

Tank: a reef aquarium with some open sand areas. Tank: an estimated minimum of about 90 litres (our estimate from the adult size and habits, not a figure from the sources), for a pair. It does not need a host anemone in captivity, and keeping its natural hosts is not recommended even for experienced aquarists, as wild-collected specimens often die. Water: the sources give no species-specific figures, so the values here are general marine aquarium guidance, not species-specific: 24–27 °C, pH 8.1–8.4 and specific gravity 1.023–1.026. Keep conditions stable with good filtration and regular water changes. Behaviour: active by day and aggressively territorial around its host, which it defends against fish such as butterflyfish. Identification: dark brown to black with an orange-yellow face and belly, a white head bar and a second white band shaped like a saddle that does not cross the whole body. Up to 13 cm. Trade: clownfish are not CITES-listed. Captive-bred fish are widely available and are the better choice where possible. The article cites a 2017 IUCN assessment without giving the category. Sources: Wikipedia, List of marine aquarium fish species (en.wikipedia.org/wiki/Listofmarineaquariumfishspecies); Wikipedia (en.wikipedia.org/wiki/Amphiprionpolymnus). Checked October 2026.

Diet

Omnivorous: zooplankton, small bottom-living crustaceans and algae. In aquaria feed frozen mysis and brine shrimp, flake, small pellets and algae-based foods.

Breeding

A protandrous hermaphrodite in a strict size hierarchy: when the female dies, the breeding male becomes female and the largest non-breeder becomes the new male. It has been bred in captivity.

Compatibility and tank mates

Reef safe. Keep one pair, away from other clownfish; generally fine with semi-aggressive and peaceful community fish of similar size.

Last updated 8 October 2026. Community-edited care guide on Aquatic-Auctions.

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