Green Mandarin Dragonet (Synchiropus splendidus)

The magnificent Green Mandarin Dragonet more commonly known as Striped Mandarinfish or Green Mandarinfish looks amazing with their combination of blue, orange, and green colors.

Males may be distinguished from females by their more-elongated first dorsal spine and are normally slightly larger. In our opinion, they are one of the most interesting and beautiful fish available to home aquarists.

Scientific Name Synchiropus splendidus
Size4” Max
Tank size30-40 Gals minimum
Reef CompatibleYes
DietCarnivore
TemperamentPeaceful
OriginWestern Pacific, Australia, Philippines
Care levelModerate
FamilyCallionymidae
Temperature72-78f
PH Level 8.1 - 8.4
Specific Gravity1.020 - 1.025
Cost$30-$50

Care

Looking at this cute small saltwater fish you’d think that it would be an easy first fish to buy. However, they need a well-established reef aquarium to thrive in. They need plenty of living rock, live sand, and plenty of hiding places and should be kept in a tank size of 30 Gallons minimum.

They are not overly aggressive but males will clash with other Male Green Mandarins.

If kept in smaller tanks with little or no hiding places and little natural food sources they will not survive. Diet is the number one killer of this fish in the home aquarium.

Diet

In the ocean they feed on pods (amphipods and copepods) in the aquarium they often starve to death because of the lack of these foods in the tank. It’s very difficult to supply them with the correct balanced diet.

That’s why it’s very important to introduce them into a well-established reef aquarium to ensure they have a constant supply of food for them to pick at throughout the day.

   Best Fish Food Guide 2019

In your home aquarium, they will feed on a variety of vitamin-enriched foods such as live brine shrimp, live black worms, and natural prey on live rock and live sand. Flake foods, pellets and dried food are now available for these types of fish ensuring a balanced diet is available but don’t rely on this as their main staple foods.

Frozen foods can be used but again they don’t often eat them, they are fussy little fish!




Pods are what they need to survive and thrive in your tank. They are very slow eaters and will need a constant supply of pods. These organisms can be found naturally in larger reef tanks.

mandarin dragonet

Don’t be put off trying to keep these fish, once you have the right environment for them to live in they will add color and character to your aquarium.

Remember a well-fed Mandarin is a peaceful Mandarin!

TOP TIP: Try and pay your Mandarin fish a little bit more attention at feeding time. Whilst the other fish are busy feeding drop a little bit of food into the quiet spot that your Mandarin will be hiding in or their preferred feeding spot.

Tank mates

It is not overly aggressive towards other fish, except for conspecifics. Introducing more Mandarins into your tank can lead to aggression and territorial fights. 

These fish live peacefully with most other species and will prefer to retreat to their hiding place rather than fight. They are considered reef tank safe but have been known to start nipping at coral polyps if insufficient food is supplied.

They are mostly bottom dwellers so making sure there aren’t too many similar bottom dwellers fish in your tank would be a good idea.

Firefish gobies make great tank mates so do Clownfish and green gobies.

Poisonous Mandarinfish

People often ask us if these fish are poisonous and the answer is… Yes!

Dragonets are covered with tiny spines ready to inject poison into anyone who tries to handle or more importantly eat them. This may sound extreme but don’t forget in the sheltered lagoons and reefs in the Pacific Ocean they can be caught by local fishermen, and like many other coral, fish are eaten as staple diets for locals.

The Green Mandarin Dragonets have two types of secretary cells, one that produces a thick mucus coating to protect it from the elements, and another that produces a toxin to protect it from predators. Not only is this toxic mucus coating dangerous, particularly if it makes it into a predator’s open wound, but reportedly, it smells disgusting.

Again, don’t let this put you off keeping one of these amazing fish. Unless you’re planning on eating it or holding it they won’t cause you or the other fish any harm.

The Mandarin fish are one of only two fish in the world that can produce it’s own amazing and striking blue colors.  Along with its close relative, the psychedelic mandarin (Synchiropus picturatus), the mandarin fish produces ‘cyanophores’ – blue pigmented, light-reflecting cells – to achieve its vibrant coloring.

The Australian Geographic magazine published a full article on this topic, which makes an interesting read.

Price & Availability

These fish are widely available in most pet store and aquarium shops. The average cost of a Green Mandarin Dragonet is around $40 with other Mandarins like the spotted Mandarin costing a little bit more. Red Scooter Mandarins are a cheaper option and are a little bit easier to feed.




The average cost of one in the UK is £30.

When purchasing a Green Mandarin Dragonet look for signs that it has been well fed in the store. A nice round belly and an all-around healthy look will indicate that they have been well fed.

Many stores struggle to feed them the balanced diet they need so many poor examples can be found. This isn’t to say all stores are like that, many have some beautiful fish on display and for sale. Ask what they have been feeding them on whilst in stock, then make sure you have a similar food source in your home aquarium to help them interrogate easier into their new home.

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