Auriga Butterfly (Chaetodon Auriga)

Also Known As: Threadfin Butterflyfish, Auriga Threadfin Butterfly

Compatibility and Behavior
The Auriga is one of the classic butterflyfish, and a good starting point if you're drawn to the family. The look is unmistakable: a bright white body crossed with bold diagonal stripes, golden-yellow dorsal and caudal fins, and a black eye band that reads like a mask, all trailing a delicate filament off the rear of the dorsal that gives it real elegance as it glides. As it matures, subtle flank patterning and a dark spot toward the back of the dorsal help set it apart from its relatives. Temperament tends to be peaceful toward fish of different shapes and colors, though it can get assertive with other butterflies or similarly shaped tankmates in tighter quarters. The honest caveat is corals, which puts it at reef safe with caution: while foraging it may pick at soft corals, LPS, clam mantles, and some sessile inverts, so it's a safer bet in a FOWLR or coral-cautious setup than a prized mixed reef. It generally settles in well alongside calm tangs, wrasses, and Anthias when introduced thoughtfully and given room to roam.

Aquarium Requirements
This is a fish that wants space and maturity, so plan around open swimming lanes and plenty of established rockwork to graze and shelter in. Small individuals around 1.5 to 2 inches do fine starting in a 75 to 90 gallon tank, while medium and large specimens are better suited to 100-plus gallon systems with long footprints and strong, stable filtration. Give it a balance of open water and structured rock zones where it can pick at natural growth and duck away when startled, along with moderate, well-oxygenated flow. Diet is also your best tool for protecting your corals: keep it well conditioned on a varied menu of mysis, finely chopped seafood, quality marine pellets, and frozen preparations, and a well-fed Auriga is far less inclined to go sampling your inverts.

Specifications
Approximate Size: Sm: 1.5–2", Md: 2.5–3.5", Lg: 3.5–4.5"
Diet: Omnivore; meaty foods such as mysis and chopped seafood, plus quality marine pellets and frozen blends
Origin: Indo-Pacific
Care Level: Intermediate
Reef Safe: With caution
Temperament: Peaceful to semi-aggressive
Minimum Tank Size: 75 gallons for small specimens, with a larger system required as it grows
Special Considerations: Reef safe with caution, as it may nip soft corals, LPS, clam mantles, and some inverts, so best in a FOWLR or coral-cautious setup; can be territorial toward other butterflyfish and similarly shaped fish