Spot Tail Dartfish are usually seen hovering a meter or so above rubble or sandy areas of the reef. They are mainly seen in pairs but occasionally they may be seen in a small group of pairs.
The Spot Tail Dartfish is found across the Indian ocean and in the west Pacific. They are found between depths of 8-50 meters. More usually they are seen around 15 to 18 meters in depth. They prefer rubble and sand to the reef. It feeds mostly on prey suspended in the water column, but will pick food off the substrate as well. The Blue Gudgeon Dartfish feeds on a diet which includes mysis shrimp, brine shrimp, table shrimp, and frozen food preparations for carnivores.