Orbicular Batfish

Geographic Origin and Biotope: Indo-Pacific. Juveniles live holed up in brackish waters, mangroves and muddy ports, exploiting incredible leaf camouflage. Adults migrate to the open sea and large reef lagoons.

Taxonomy and Morphology: Orbicular Batfish (Platax orbicularis). Marine Batfish. It grows out of all proportion (50 cm / 20 inches), transforming from an almost oval "flat leaf" (juvenile form) into a majestic silver disc (orbicular).

Social Behavior: The Pet (Puppy-dog tame). Once accustomed, the Batfish is highly intelligent and peaceful; it will take food directly from the aquarist's hands, skimming the surface as soon as you approach the glass.

Coloration and Sexual Dimorphism: Excellent camouflage. The juvenile has disproportionately high dorsal and anal fins colored rusty brown/black: if threatened, it pretends to be a dead leaf carried by the current. The adult is round, shiny silver, with only a few faded bands on the eyes and sides.

Aquarium Setup: Monster Tank (at least 800-1000 Liters / 210-260 Gallons for an adult, tank taller than long). Given its "disc" size, shallow tanks will force it to scrape its fins on the rocks or bottom. There must be no narrow crevices.

Diet and Feeding: Voracious omnivore. Organic debris machine, in nature it cleans the water. In the tank it must be stuffed with minced shrimp, squid pulp, bluefish (silversides) and also vegetables (broccoli, spinach, nori algae).

Water Quality: Tolerates sub-optimal quality well (coming from mangroves), but as it grows it will produce a terrifying organic load. The filters must be "shark" class to handle the ammonia produced.

Compatibility and Tankmates: Prey and Predator. Although not mean, it will eat any crustacean and fish small enough to fit in its mouth (Chromis, dwarf Clowns). Juveniles (with their very high fins) are instead perfect victims of bites from Angelfish and Triggerfish.

Aquarium Reproduction: Absent in private systems. They reproduce only in the oceans releasing pelagic eggs in large schools; some public aquariums and Asian farms (food-fish) succeed in huge brackish ponds.

Risks and Diseases: The Unsuitable Giant. Often sold "cute" at 5 cm (2 inches) in stores, many beginners put it in 100 liters (25G). In 1 year it doubles in size 10 times. If confined in cramped tanks, its fins will rot and it will die prematurely.