The Green Mandarin Dragonet is one of the most recognizable small reef fish in the hobby, wearing a blue-to-green body traced with irregular orange and red wavy lines. It is a benthic species from the Western Pacific, ranging from the Ryukyu Islands south to Australia, where it occupies shallow protected lagoons and inshore reefs, typically over silty bottoms interrupted by coral and rubble. Adults reach roughly 4 inches. Males are readily identified by an elongated first dorsal spine and a noticeably bulkier build than females.

Housing should be built around a mature, biologically stable marine aquarium with abundant live rock that provides cover, hunting surfaces and a self-sustaining population of copepods and amphipods. Open areas of sand or rubble let the fish forage the way it does on the reef, though sand, crushed coral or bare bottom can all work provided the rockwork supplies enough feeding habitat. A minimum of 30 gallons is commonly published, but tank age and sustainable prey production matter far more than nominal volume, and many keepers succeed only in larger, pod-rich systems. A refugium is a valuable addition because it shelters and replenishes live food. Moderate flow suits the species, and a secure lid, while not strictly required, is a sensible precaution.

This is a Difficult species, and that rating is driven almost entirely by nutrition rather than water chemistry or disease sensitivity. A newly established aquarium will not support one. Give the system many months to develop a dense microfauna population before introducing a mandarin, and plan for how that population will be sustained over the long term.