Undulate Triggerfish (Balistapus undulatus)

Undulate Triggerfish (Balistapus undulatus) known to tropical fish keeping enthusiasts as the Orangelined Triggerfish, Balistapus undulatus, Orangelined – Orangetailed Triggerfish, and Orange-Lined Triggerfish is a demersal species that occurs on coral reefs in tropical marine waters of the Indo-western Pacific.

The Undulate Triggerfish‘s range extends from the coast of East Africa, the Red Sea, Japan, and in Western Australia; from the central to north-western coast, and the entire length of the Great Barrier Reef south to northern New South Wales.

Both juvenile and adult Orangelined Triggerfish have been found at depths to over 160 feet, but they prefer living in the shallower coral reefs, coral lagoons, and external reef slopes at depths from 6 to 35 feet.

Adult Undulate Triggerfish are normally found around their burrows and dens among rock and branching corals, while juveniles prefer softer corals.

The Undulate Triggerfish is an omnivorous demersal species that because of its broad distribution and varied benthic diet is a critical component in coral reef ecosystems. They feed on molluscs, crustaceans, ctenophores, cnidarians, echinoderms, algae, small fish, and are a dominant predator of Echinometra mathaei, the burrowing sea urchin, which can if left unchecked totally degrade a flourishing coral reef ecosystem.

Undulate Triggerfish (Balistapus undulatus)

The Undulate Triggerfish has a stocky, laterally compressed, oval shaped body with a large head, a small mouth, and strong teeth. They have an attractive dark brown to emerald green body with orange lines that begin behind the head and cover the entire body. They have an orange caudal fin with a large black spot at the base of their peduncular spines.

Male Undulate Triggerfish are generally larger than females and do not have concave

Undulate Triggerfish (Balistapus undulatus)

snouts. Juvenile fish and females are smaller and have concave snouits. Males lose the orange lines around their snout as they mature.

Because of its belligerent attitude, the Undulate Triggerfish is best housed in a mature FOWLR aquarium of at least 125 gallon capacity with a sandy of fine coralline gravel substrate and copious amounts of live rock arranged into crevices, overhangs and caves for them to hide among. They are NOT reef safe and should be the only trigger in a fish only aquarium.

Undulated Triggerfish will thrive best either on its own or with other similarly sized, semi-aggressive to aggressive tankmates. They can be shy when first introduced into a community tank but will quickly get over their shyness and eventually attack other less aggressive tankmates, especially triggerfish.

Undulate Triggerfish have not been bred in an aquarium environment.

In their natural habitat, Orangelined Triggerfish are carnivores that feed on fish, mollusks, corals, crustaceans, ctenophores, cnidarians, algae, and especially echinoderms. In an aquarium environment they should be fed a varied diet of fresh or frozen shrimp, squid, clams, small fish, krill, hard shelled rock shrimp as well as some marine algae and vitamin-enriched herbivore foods.

Undulate Triggerfish (Balistapus undulatus) is readily available to tropical fish keeping enthusiasts from a variety of online suppliers and specialty fish shops at reasonable prices that vary according to size and area of collection.

Approximate Purchase Sizes: Under 2″; Medium: 2″ to 4″; Large: 4″ or Higher. Medium size Indonesian prices start at $89.99.

Undulate Triggerfish (Balistapus undulatus)

Minimum Tank Size: 125 to 180 gallons
Aquarium Type: FOLR
Care Level: Easy
Temperament: Aggressive
Aquarium Hardiness: Hardy
Water Conditions: 72-78° F, dKH 8 – 12°, pH 8.1 – 8.4, sg 1.020-1.025
Max size: 12″
Color Form: Black, Blue, Green, Orange, Yellow
Diet: Carnivore
Compatibility: Reef NO
Origin: Indo-West Pacific and Hawaii
Family: Balistidae
Lifespan: 8 – 10 years
Aquarist Experience Level: Intermediate