The Mandarin Dragonet (Synchiropus splendidus) is one of the most iconic saltwater aquarium fish. For those new to the hobby, it's likely one of the first fish beyond the clownfish on the must-have list. Once considered an "expert only" fish, the Mandarin Dragonet has become relatively easy to keep thanks to captive breeding efforts. With their stunning coloration, peaceful temperament, and unique feeding behavior, they’re a fascinating addition to a well-established reef tank.

Ultimately, success with this fish hinges on your ability to meet its dietary needs. While water quality, tank size, and peaceful tank mates are all important, consistent access to appropriate food is what truly determines whether your Mandarin thrives or fades.

It's important to note that this care guide focuses specifically on the Synchiropus splendidus species, commonly seen in both Blue (sometimes called Green) and Red color variants. A closely related species, the Synchiropus picturatus (commonly called the Spotted or Psychedelic Mandarin), shares nearly identical care requirements but is not the focus of this care guide.

General Habitat & Tank Requirements:

  • Tank Size: A minimum of 30 gallons.
  • Aquascape: Live rock formations provide excellent cover, security, and natural hunting grounds.
  • Substrate: No specific substrate is required, and they adapt well to sand, crushed coral, or bare-bottom setups.

Water Conditions:

  • Temperature: 75°F to 80°F (23°C to 27°C).
  • pH: 7.7 to 8.5.
  • Specific Gravity (Salinity): 1.020 to 1.026.
  • Water Quality: Maintain ammonia and nitrite levels at 0 ppm, and nitrates below 20 ppm.
  • Filtration: Employ high-quality filtration, such as a protein skimmer, to ensure optimal water quality.
Mandarin Dragonet
Mandarin Dragonet

Diet and Feeding

Feeding is the single most important, and often most challenging, aspect of caring for a Mandarin Dragonet. These fish are constant foragers in the wild, spending their days picking at tiny crustaceans like copepods hidden among the live rock. Replicating that behavior in an aquarium is critical for their long-term health.

Captive Bred vs. Wild Caught

Thanks to advancements in sustainable aquaculture, captive bred Mandarin Dragonets have become common and are far easier to feed then their wild counterparts. In many cases, captive bred specimens are already trained to accept frozen and prepared foods such as:

While they'll still hunt for live copepods between feedings, captive bred Mandarins are a much more sustainable and practical option for hobbyists.

Wild Caught Challenges

Wild caught Mandarins, on the other hand, often refuse anything other than live copepods. This means hobbyists must maintain a thriving population of pods in the tank or provide a continuous external source, such as a separate refugium or regular additions of live copepods. Failure to provide enough food can lead to starvation, even in seemingly healthy tanks.

Behavior and Compatibility

Mandarins are peaceful fish that can coexist with a variety of tank mates.

Compatible Tank Mates

  • Fish: Clownfish, Gobies, Angelfish, Cardinalfish, most Wrasse, Firefish, Tangs, and other peaceful fish.
  • Invertebrates: Safe with inverts.
  • Coral: Dragonets are considered Reef Safe and can be kept with Soft, LPS, or SPS coral.

Behavioral Notes

Mandarin Dragonets are somewhat timid fish and are susceptible to being bullied by other tank mates. They can be slow eaters, so take care when feeding to make sure they get their fair share of food. They are best kept singly or as a mated pair.