Half Moon Trigger (Sufflamen albicaudatus)

The Half Moon Trigger is one of the most commanding and characterful triggerfish available in the marine hobby. Sufflamen albicaudatus is the Red Sea endemic sister species to the broader Indo-Pacific Halfmoon Triggerfish, and it shares all the traits that make the Sufflamen genus so compelling: a deep brownish-black body that transitions into a striking royal blue chest and throat, a bold yellow vertical bar running beneath each eye, and the species' signature white-tipped caudal fin that gives it both its scientific name and its most recognisable feature. Broad, laterally compressed, and built for power, this is a fish that fills a tank with presence. Triggerfish are intelligent, interactive, and genuinely engaging to keep, learning to recognise their keeper, anticipate feeding, and occasionally vocalise with audible grunting sounds that catch new hobbyists completely off guard. This is a serious fish for serious systems, best suited to experienced keepers running large, well-matched FOWLR setups where its aggression, appetite, and habit of rearranging the furniture can be managed on its own terms.

Why we love it

• Striking colour combination of deep brown-black body, vivid royal blue chest and throat, yellow eye bar, and white-tipped tail is distinctive and dramatic in any large display
• One of the most interactive and keeper-aware fish available in the hobby; learns quickly, anticipates feeding, and responds to its keeper in ways that genuinely blur the line between fish and personality
• Audibly vocalises with a grunting sound during feeding and when excited, a trait that surprises and delights anyone who has not kept a triggerfish before
• Hardy, long-lived, and exceptionally durable once established; a well-kept specimen can thrive for a decade or more
• A Red Sea endemic that is less commonly encountered in the trade than its Indo-Pacific counterpart, making it a sought-after and distinctive addition to a large display

Suggested parameters

• Temperature: 22–26°C (72–78°F)
• Salinity: 1.020–1.025 SG
• pH: 8.1–8.4
• Alkalinity: 8–12 dKH
• Ammonia/Nitrite: 0
• Nitrate: Under 30 ppm; strong biological filtration and a capable protein skimmer are essential given this species' substantial bioload

Care and temperament

• Difficulty: Moderate
• Temperament: Aggressive. The Half Moon Trigger is assertive, territorial, and will increase in boldness as it matures; juveniles are considerably more manageable than adults, and keepers should plan for the fish's long-term personality rather than its current one
• Reef safe: No. Will consume all motile invertebrates, disturb and destroy corals through foraging and physical manipulation, bite equipment and air lines, and actively rearrange rockwork and substrate. Strictly a FOWLR species
• Minimum tank size: 125 gallons, with 150 gallons or larger strongly preferred for long-term keeping; tank length and open swimming volume matter as much as raw gallonage

Diet

The Half Moon Trigger is a powerful, enthusiastic carnivore with strong jaws built for cracking hard-shelled prey, and its diet should reflect that.

• Frozen krill, squid, clam, silversides, and other meaty marine preparations form the core diet
• Hard-shelled foods including whole shrimp, clams in shell, and occasional live or frozen urchin are important for naturally wearing down the triggerfish's continuously growing teeth; teeth that are not worn down adequately can eventually overgrow and interfere with feeding
• Small seashells and pieces of rubble placed in the tank give the fish something to bite and turn over between feedings, which serves the same purpose and provides behavioural enrichment
• High-quality carnivore pellets accepted readily by most individuals and are a convenient supplement to frozen and whole prey items
• Feed once to twice daily; do not place hands in the tank during feeding as this species will bite, and boldness around hands increases significantly with age

Compatibility and tankmates

• Suitable only for large, robust, assertive fish that are not easily intimidated or outcompeted: large angelfish, tangs, groupers, large wrasses, snappers, squirrelfish, and moray eels are appropriate companions
• Only one triggerfish per system is strongly recommended; inter-triggerfish aggression is intense and typically ends badly
• Avoid housing with lionfish and other slow-moving, passive predators that are vulnerable to fin nipping and persistent harassment
• Will eat all ornamental shrimp, crabs, snails, sea stars, urchins, and any other motile invertebrate in the system without hesitation
• Should be the last fish added to the aquarium; once established it will challenge any new additions aggressively, and introductions of new fish to an established Half Moon Trigger require careful planning
• Provide rockwork with wide caves and crevices; triggerfish lock themselves into shelter using their dorsal spine when threatened and need access to appropriate refuge points

Health and acclimation notes

The Half Moon Trigger is one of the hardiest fish available in the marine hobby and typically settles and begins feeding within the first day or two of introduction. Its main long-term health concern is dental overgrowth: without regular access to hard-shelled foods and something to bite, the teeth can grow to a point where feeding becomes difficult. Providing shell fragments, whole crustaceans, and hard prey items as a regular part of the diet prevents this. This species is known to bite equipment, airline tubing, heater guards, and anything else it can reach, so all in-tank equipment should be secured or protected. Rockwork must be stable and braced, as this fish will deliberately move rocks and rubble during foraging and can cause rockslides in improperly structured aquascapes. Quarantine before introduction to an established display is always recommended. A secure, tight-fitting lid is important as triggerfish can be surprisingly capable of pushing through loose-fitting covers.

What you are buying

• You will receive: 1 Half Moon Trigger (Sufflamen albicaudatus)
• Colouring can vary between individuals and intensifies with age; juveniles show a darker, more uniform body tone that develops into the full adult colouration with maturity
• Size and exact patterning may vary; please see size options at checkout
• As with all triggerfish, personality varies between individuals; some specimens are notably bolder and more assertive than others of the same species