Orangespot Filefish (Oxymonacanthus Longirostris)

Also Known As: Orange-Spotted Filefish, Harlequin Filefish

Compatibility and Behavior The Orangespot Filefish is one of those genuinely unique reef oddballs that experienced hobbyists go out of their way to track down. It's truly one of the only species you can add to your tank featuring this incredible colorway. The slender, laterally compressed body is patterned with countless bright orange spots over a pale light-green background, finished with a pointed snout, expressive eyes (featuring an incredible kaledescopic pattern), and a tall first dorsal spine that the fish can raise and lower at will. The soft dorsal and tail fins undulate gently as it drifts around branching corals and rockwork, giving it an almost hovering quality in the water. Behavior-wise this is a shy to moderately peaceful species that does best alongside calm, non-aggressive tankmates that won't outcompete it at feeding time. It's considered reef safe with significant caution. In nature, this fish feeds heavily on coral polyps, particularly Acropora, and in captivity many individuals continue to nip SPS and sometimes other small-polyp corals even after they've accepted prepared foods. In a thoughtfully planned system, the Orangespot becomes a fascinating, always-on-display specialist, but it's really a species for experienced aquarists who are comfortable with both the dietary and reef-safety challenges.

Note on sexing: Due to their rarity, we cannot guarantee male or female specimens of this species if requested.

Aquarium Requirements Plan on a mature, stable aquarium with branching live rock or coral skeletons that provide both grazing surfaces and a sense of security. A peaceful environment with gentle to moderate flow and plenty of nooks, crevices, and shaded areas helps the fish settle in and display its natural slow-cruising behavior. Because Orangespots are specialized coral feeders, long-term success usually depends on patient acclimation to alternative foods and maintaining excellent water quality while offering frequent small feedings throughout the day. Most keepers have the best results in SPS-light or carefully chosen mixed reefs, or in species setups where any potential coral nipping is acceptable from the start. Offer a varied diet of frozen mysis shrimp, finely chopped marine foods, small zooplankton-type frozen blends, and quality micro-pellets. Some keepers also choose to offer sacrificial or test coral frags to cater to the natural feeding habits, which can help with long-term acclimation.

Specifications
Approximate Size: 1.5-3"
Diet: Specialized omnivore (naturally feeds on coral polyps; may accept frozen mysis shrimp, finely chopped seafood, small zooplankton-type blends, and micro-pellets in captivity)
Origin: Indo-Pacific
Care Level: Expert (best for experienced aquarists due to specialized diet and reef-safety concerns)
Reef Safe: With strong caution (known to nip SPS, especially Acropora, and possibly other corals)
Temperament: Peaceful
Minimum Tank Size: 50 gallons
Special Considerations: Coral feeder that may continue nipping SPS even after accepting prepared foods; best suited to SPS-light reefs, carefully chosen mixed reefs, or dedicated species setups; requires patient acclimation and frequent small feedings