Ruby Red Dragonet (Synchiropus sycorax)
• Small fish safe: ✅ Yes
• Small invert safe: ✅ Yes
• Coral safe: ✅ Yes
• Minimum tank size: 110 liters (30 gallons)
• Adult size: Up to 6 cm (2.5 inches)
• Diet: Obligate carnivore, primarily feeding on copepods and amphipods
• Be aware of: Requires a well-established aquarium with a healthy population of live microfauna; can be difficult to feed; males may be territorial toward one another
Appearance and Coloration
The Ruby Red Dragonet is one of the most stunning dragonets, featuring a brilliant ruby-red body covered in tiny white spots. Males display an elongated first dorsal fin, decorated with bold black and yellow bands edged in blue, while females have a more subdued appearance with a smaller dorsal fin. The vivid yellow pectoral fins add a striking contrast to its overall coloration, making this species highly desirable among marine aquarists.
Natural Habitat and Behavior
Synchiropus sycorax is native to the Philippines, particularly around Jolo Island in the Sulu Archipelago. It inhabits coral rubble zones and mixed reef environments at depths of up to 38 meters (125 feet).
Like other dragonets, Ruby Red Dragonets are benthic dwellers, meaning they spend most of their time on the substrate, using their enlarged pectoral fins to “scoot” along the bottom. They are slow, deliberate feeders, constantly searching for tiny invertebrates hidden in the sand and rockwork.
This species is peaceful but can be territorial toward conspecific males. In the wild, they live in loose social structures, with a single dominant male overseeing a harem of females.
Tank Requirements and Water Parameters
• Minimum Tank Size: 30 gallons (110 liters)
• Water Parameters:
• Temperature: 24°C – 27°C (75°F – 81°F)
• pH: 8.1 – 8.4
• Specific Gravity: 1.020 – 1.025
• Aquascaping:
• Plenty of live rock to provide hiding places and natural foraging areas.
• A mature refugium is recommended to sustain a stable copepod population.
• A sandbed can help support natural prey items like micro-crustaceans.
• Lighting: Moderate; they do not require intense reef lighting.
• Water Movement: Low to moderate; they are weak swimmers and prefer gentle currents.
Diet and Feeding
Ruby Red Dragonets are obligate micro-crustacean feeders, meaning they must have access to live copepods and amphipods.
• Natural Diet: Benthic micro-crustaceans (copepods, amphipods, small worms).
• Captive Diet:
• Live copepods and amphipods (essential for long-term success).
• Enriched baby brine shrimp (only a temporary supplement).
• Frozen foods (mysis shrimp, fish roe, cyclops plankton)—only if trained.
• Some may accept pellets or prepared foods, but this is rare.
Feeding Considerations:
• Mandarins require continuous grazing, unlike other fish that eat in single feedings.
• A refugium is strongly recommended to provide a sustainable food source.
• If the aquarium does not support a large copepod population, regular supplementation with bottled copepods is necessary.
Compatibility and Social Structure
• Temperament:
• Extremely peaceful and non-aggressive, making them excellent for community tanks.
• Males will fight if housed together, so only one male should be kept unless in a very large system.
• Tank Mates:
• Ideal companions include gobies, blennies, clownfish, peaceful wrasses, and other slow-moving species.
• Avoid aggressive feeders like dottybacks, damsels, and large wrasses, as they can outcompete dragonets for food.
• Reef Compatibility: 100% reef-safe—does not bother corals or invertebrates.
Important Considerations
• Difficult to Keep: Not recommended for beginners due to feeding challenges.
• Require a Mature Tank: Needs an established aquarium with a large, self-sustaining copepod population.
• Avoid Starvation: Many die from starvation due to lack of suitable live food. Regularly monitor body condition for signs of malnutrition (sunken belly, lethargy).
• Pairing: A male-female pair can be kept if introduced together, but two males will likely fight.