Rhinecanthus assasi

(Forsskal, 1775)

Picasso Triggerfish, Assasi Triggerfish, Arabian Picasso Triggerfish

Range: Western Indian Ocean: Red Sea to Gulf of Oman and Persian Gulf

Size: 12 inches (30 cm)

Natural Environment: Inhabits shallow sandy and rubble areas on inshore coral reefs. Seeks caves or coral branches to hide or rest during evening hours. Feeds on urchins, crustaceans, mollusks, smaller fish and tubeworms.

General Husbandry: In general, an extremely hardy and pretty looking species, having a upper tan body, white lower half, several blue black bands across the top of the head between the eyes, several dark horizontal stripes near the tail, yellow lips, blue vertical stripe below the eyes, and a tan stripe running from cheek to cheek.

In the home aquarium, they require a meaty diet, e.g., chopped fish, shrimp, squid, and clam flesh, and/or meaty type frozen carnivore foods with two or three feedings per day highly recommended. As to its environmental needs, provide enough rocky caves for it to hide or sleep in. Should only be maintained with larger more aggressive fish, such as large moray eels, snappers, angelfish, tangs or other larger fish that can defend themselves, yet not lionfish, as they are too slow moving and a target for fin nipping. May also re-aquascape your aquarium and make a mess of the sandbed due to its constant searching for infauna/invertebrates. Will also bite the hand that feeds it, so do not place your hands in the aquarium! May be fairly peaceful as a juvenile, yet can get more aggressive with age. Keep in mind that generally its recommended not more than one triggerfish be kept per aquarium unless a mated pair, and furthermore, that it be the last fish to be placed into the aquarium. Yet more than one of this species/genera can be maintained, with caution, in the same aquarium if the aquarium is large enough and all are introduced at the same time.

Taxonomy:

Order: Tetraodontiformes

Suborder: Tetraodontoidei

Family: Balistidae

Genus: Rhinecanthus

FYI: Their common name, triggerfish, comes from their ability to lock and unlock their first dorsal fin. This fin is normally retracted and carried in a groove on the upper body. When frightened, the fish will dart into a crevice or branch of coral and raise this trigger-like fin, securely locking itself into its place of protection.

They should be housed with small pieces of seashells since they like to bite on them or turn them over in the search of prey. Better these shells than other aquarium decor. It also helps keep their teeth worn-down, which actually could get too long and pointed and cause them some difficulty in feeding.

In general, triggerfish are like angelfish and surgeonfishes, as they have laterally compressed bodies with small mouths with strong jaws and chisel-like teeth for crushing hard-shelled prey. However, eyes are set back and located high on their large head to avoid damage when feeding on urchins, one of their favorite foods.

Preys on sea urchins by squirting water from the mouth under them to overturn, then attacks its meaty underside.

Even though specimen and confines specific, those in the genera Balistes, Balistoides, Pseudobalistes, Rhinecanthus, and Sufflamen are generally thought of as the most aggressive in the Triggerfish family. Those in the Melichthys, Odonus and Xanthichthys genera are more suitable community fish candidates, yet all are not trust worthy when it comes to invertebrates as mentioned above.

Care Level: Easy

Temperament: Aggressive

Diet: Carnivore

Acclimation Time: 15 minutes+

Aquarium Environment: Fish-only aquarium

Coral Safe: No

Invertebrate Safe: No

Tankmates: Equal in size or larger/will attack/eat smaller fish

Minimum Tank Size: 100 gallons

Temperature Range: 72 - 82°F (22 – 27°C)

Specific Gravity: 1.020-1.026

pH: 7.9 - 8.5