Green Clown Goby Care Guide
Gobiodon histrio is a tiny green coral goby of the Indo-West Pacific that perches on Acropora and releases a toxin to deter predators.
Compiled by Aquairi from published sources · Published · Updated
Overview
Gobiodon histrio, the Green Clown Goby, is a very small marine coral goby of the Indo-West Pacific. FishBase describes a mainly green body with red to violet stripes or broken lines, four to five reddish bars on the head, and no scales. It is a coral-commensal species that lives among the branches of Acropora corals and is capable of facultative air-breathing. It was described by Valenciennes in 1837.
Taxonomy
- Family: Gobiidae
- Genus: Gobiodon
- Scientific name: Gobiodon histrio
Habitat
FishBase records the species from the Red Sea to Samoa, north to southern Japan and south to the Great Barrier Reef. It lives among Acropora branches on reef crests and in lagoons, usually at depths of 2 to 15 m.
Tank requirements
- Minimum tank volume: 50 L
- Temperature: 24-26 °C (75-79 °F)
- pH: 8.1-8.4
- Specific gravity: 1.024-1.026
- Carbonate hardness: 8-12 dKH
- Maximum size: about 3.5 cm
- Lifespan: 3-6 years
Diet
A carnivore. In the aquarium it accepts small meaty foods such as cyclops, enriched brine shrimp and finely chopped mysis, fed twice daily.
Compatibility
Lives solitary or in pairs and is otherwise peaceful. It suits calm companions such as clownfish, cardinalfish and wrasses; lionfish and other predators should be avoided. Wikipedia notes that when disturbed it releases compounds that impair the locomotion of other fish, deterring predators.
Reef compatibility
Reef-safe with the caveat that it perches on branching Acropora and may occasionally nip at small-polyp stony coral polyps. Wikipedia reports a mutualistic relationship in which it consumes toxic Chlorodesmis algae that damages its host Acropora nasuta.
Conservation status
IUCN Red List: Least Concern (assessed 15 August 2023).
Gobiodon histrio Breeding Guide
Overview
Gobiodon histrio (Valenciennes, 1837) is a small reef goby native from the Red Sea through the western Pacific to southern Japan, Samoa and the Great Barrier Reef (Wikipedia). It reaches about 3.5 cm total length and lives at depths of about 2 to 15 m in a mutualistic relationship with the coral Acropora nasuta. The fish perches within the coral branches, which serve as shelter and spawning substrate.
Sexing
G. histrio can change sex in either direction: when two gobies of the same sex colonise a new coral patch, one of them changes to the opposite sex (Wikipedia). This bidirectional flexibility makes fixed external sexing unreliable, so pairs are formed simply by housing two compatible fish on a shared coral and letting one transition.
Conditioning
Conditioning depends on stable reef water and regular small carnivore feeds such as enriched mysis and finely chopped marine foods. A pair that has claimed a branched host coral and perches together within it shows the settled territorial behaviour that precedes spawning.
Breeding Setup
Because the species is naturally associated with Acropora nasuta, a breeding setup should provide branched Acropora or a comparable branched structure where the pair can shelter and deposit eggs on the branches. A mature reef tank with stable parameters and gentle flow best supports the host coral and the goby pair together.
Spawning Behavior & Trigger
Detailed spawning behaviour, clutch size and triggers specific to G. histrio are not given in the cited reference. As in related coral gobies, eggs are expected to be demersal and laid on the coral branches with male attendance, but those specifics are not documented here and so are omitted rather than assumed.
Egg & Fry Care
No species-specific account of egg guarding duration or larval rearing for G. histrio appears in the cited source. The skin of this goby produces a toxin that deters predators by impairing their locomotion (Wikipedia); this chemical defence protects adults but offers no documented shortcut for raising the small planktonic larvae.
Common Challenges
The limiting step is larval rearing, which is not documented for this species in the cited source. Coral gobies also nip host polyps, and the toxic skin mucus, while protective, can stress tankmates if a fish dies in a small system; both factors argue for a dedicated, well-monitored breeding tank.