Saddleback Anemonefish Care Guide
Amphiprion polymnus is a western Pacific anemonefish with a dark body, two white bars and a saddle marking. It pairs closely with the carpet anemone Stichodactyla haddoni.
Compiled by Aquairi from published sources · Published · Updated
Overview
Amphiprion polymnus, the saddleback anemonefish, is a reef-associated damselfish of the family Pomacentridae. It has a dark body crossed by two white bars, the second of which is broken into a distinctive white saddle. It reaches a maximum length of about 13 cm.
Taxonomy
- Family: Pomacentridae
- Genus: Amphiprion
- Scientific name: Amphiprion polymnus (Linnaeus, 1758)
Habitat
The species ranges across the western Pacific from the Ryukyu Islands of southern Japan through the Philippines, Indonesia and New Guinea to northern Australia and the Solomon Islands. Adults inhabit silty lagoons and harbour areas at depths of about 2 to 30 m. It associates with the carpet anemone Stichodactyla haddoni and, more rarely, Heteractis crispa.
Tank requirements
- Minimum tank volume: 150 L
- Temperature: 24-26 °C (75-79 °F)
- pH: 8.1-8.4
- Carbonate hardness (dKH): 8-12
- Specific gravity: 1.024-1.026
- Lifespan: 12-14 years
Diet
Amphiprion polymnus is an omnivore whose diet is based on zooplankton, small benthic crustaceans and algae, with a trophic level of 2.7. In the aquarium it accepts marine flake and pellet foods plus frozen mysis and brine shrimp, fed about twice daily.
Compatibility
This diurnal species occupies the middle water column, is aggressively territorial and depends on its host anemone for shelter. It can be kept with tangs, royal gramma, wrasses and cleaner shrimp, while other clownfish species and aggressive predators such as triggerfish should be avoided.
Reef compatibility
Amphiprion polymnus does not eat coral and is reef-safe. Because it naturally associates with a sand-dwelling carpet anemone, it does best in a system with an open sand bed. It is maintained at reef salinity of 1.024-1.026 specific gravity and carbonate hardness around 8-12 dKH.
Breeding
The species is a monogamous protandrous hermaphrodite: the breeding male changes sex to female if the sole female dies. Eggs adhere to the substrate and are guarded and aerated by the male until they hatch.
Conservation status
IUCN Red List: Least Concern (assessed 2010).
Saddleback Anemonefish (Amphiprion polymnus) Breeding Guide
Overview
Amphiprion polymnus is a demersal egg-layer that is regularly captive-bred. FishBase records it as oviparous with distinct pairing, the eggs demersal and adhering to the substrate, and the male guarding and aerating them. It is a protandrous hermaphrodite with a recorded length at sex change of about 9.2 cm, so the largest fish becomes the female and the breeding male can change sex if she is lost.
Sexing
Sex is determined by size and social rank rather than colour. In a pair the female is the larger fish and the breeding male is smaller; FishBase gives a length at sex change near 9.2 cm. A lone fish functions as a male and will become female when paired with a smaller one, so pairing two juveniles and letting the dominant one mature into the female is the most reliable route to a breeding pair.
Conditioning
Condition the pair on frequent, varied marine feedings and stable water. The species lives in silty lagoons and harbours and almost always associates with the anemones Heteractis crispa and Stichodactyla haddoni; offering a host anemone, particularly S. haddoni, lowers stress and encourages a steady spawning routine.
Breeding Setup
Provide the pair their own territory with a flat hard surface near the host anemone, where the female deposits eggs on a cleaned patch close to the anemone. Keep stable reef parameters; the record lists about 24-26 degrees Celsius and pH 8.1-8.4, and FishBase gives a wild depth of roughly 2-30 m. The pair clean and defend the nest before spawning.
Spawning Behavior & Trigger
The female lays a clutch of conical eggs (clownfish lay up to about a thousand, each 3-4 mm long) which the male fertilises and then tends, cleaning, guarding and fanning them with his pectoral fins. The eggs start bright orange and darken as the embryos and eyes develop. Settled, well-fed pairs spawn on a regular repeating cycle near the host anemone.
Egg & Fry Care
Incubation lasts six to seven days and the larvae hatch at night. The newly hatched larvae pass through a pelagic stage of up to about 12 days before settling, during which they must be reared separately on appropriately small first foods such as rotifers, advancing to larger live foods as they grow. They are far too small to take adult food at hatching.
Common Challenges
The pelagic larval phase is the principal hurdle: the minute larvae require clean rearing water and correctly sized live first foods or mortality is high. The species is semi-aggressive, so a poorly matched pair may fight. Transferring the egg-bearing surface or the freshly hatched larvae to a dedicated rearing tank protects them from predation in the main display.