Triangle Butterfly EXPERT (Chaetodon Triangulum)

Also Known As: Triangle Butterflyfish, Red Sea Butterflyfish

Compatibility and Behavior
This is a collector's fish, and it asks a lot in return. The Triangle Butterfly is uncommon in the trade, and in the wild it's an obligate coral feeder that grazes heavily on polyps and small benthic inverts. That one fact drives everything about keeping it: this is an expert-level fish with specialized dietary needs and a real sensitivity to any wobble in water quality, acclimation, or overall stability, and it's not a butterfly to cut your teeth on. What you get for the effort is something special, a beautifully gradiented body marked with bold triangular patterning, dark facial accents, and soft yellow tones that add up to a genuinely refined profile. On reef safety it separates itself from the rest of the family: because it feeds on coral, this isn't a "with caution" fish but a straightforward not-reef-safe one, best kept in a species-focused or expert-managed system rather than turned loose in a mixed reef. Temperament is peaceful toward dissimilar tankmates, but it's easily stressed and does poorly housed with aggressive or overly boisterous fish, so a calm, deliberate stocking plan matters as much as the tank itself.

Aquarium Requirements
Everything here comes back to stability and feeding. Give it a mature, well-established tank of 90 gallons or more for small to medium individuals, with a long footprint, excellent water quality, strong filtration, and well-oxygenated flow. This is not a fish for a young system, since sudden shifts in salinity, pH, or nutrients hit it hard. Feeding is the real commitment: as a specialized coral grazer it needs frequent, deliberate meals, several times a day, of enriched mysis, finely chopped seafood, and frozen specialty blends, and even then meeting its nutritional needs consistently takes work. Go in understanding this is a delicate, demanding feeder that rewards experience and punishes shortcuts.

One important note on live arrival: because of its specialized coral-based diet and environmental sensitivity, we guarantee the Triangle Butterfly for live arrival only. Please be sure your system and feeding plan are ready before ordering.

Specifications
Approximate Size: Sm: 1.5–2.5", Md: 2.5–3.5"
Diet: Specialized coral feeder; coral polyps, benthic invertebrates, enriched mysis, frozen specialty blends, and finely chopped seafood
Origin: Indo-Pacific
Care Level: Expert
Reef Safe: No
Temperament: Peaceful to semi-aggressive
Minimum Tank Size: 90 gallons
Special Considerations: Rare in the trade and an obligate coral feeder, making it an expert-only fish with a highly specialized diet; very sensitive to unstable conditions and guaranteed for live arrival only; not reef safe, as it feeds on coral polyps