Jewel damsel (Microspathodon chrysurus) care guide

Group
Marine fish
Other names
Yellowtail damselfish
Family
Pomacentridae (damselfishes)
Origin
Tropical western Atlantic, including the Caribbean coast of Panama; coral reefs.
Water
saltwater
Maximum size
20 cm
Temperature
24–27°C
pH
8.1–8.4
Hardness
Salinity SG 1.023–1.026
Minimum tank
200 litres
Care level
intermediate
Temperament
aggressive
Reef safe
yes

Care

Tank: a large fish-only or robust reef aquarium with rockwork and algae to graze. Tank: an estimated minimum of about 200 litres (our estimate from the adult size and habits, not a figure from the sources), given its size and aggression. 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: among the largest and most aggressive damsels; it uses its size to dominate feeding areas. Parental males sometimes eat their own clutches. Identification: juveniles are dark blue with bright blue spots ("jewels"); adults are dark with a yellow tail. The list gives up to 20 cm; the article gives no length. Trade: collected on a small scale for the aquarium trade. IUCN: Least Concern. Not CITES-listed. Sources: Wikipedia, List of marine aquarium fish species (en.wikipedia.org/wiki/Listofmarineaquariumfishspecies); Wikipedia (en.wikipedia.org/wiki/Microspathodonchrysurus). Checked October 2026.

Diet

Omnivorous, with the diet changing with age: young adults take cnidarian tissue and zooxanthellae; adults mainly graze blue-green algae (cyanobacteria) but eat other plentiful food. Offer algae-based foods, nori and some meaty frozen foods.

Breeding

Spawning starts at sunrise and lasts about an hour. Males prepare nests on dead coral and guard and aerate the eggs, which hatch on the morning of the sixth day. Breeding peaks between full and new moon.

Compatibility and tank mates

Reef safe per the list, but young fish feed on cnidarian tissue, so watch soft corals and anemones. Very aggressive: keep with large, robust tankmates only.

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

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