Spotted Mandarin Care Guide: Tank Size, Diet, Copepods & Tankmates
Spotted Mandarin care made simple: how big a tank it needs, why copepods matter so much, whether it eats frozen food, and which fish make safe tankmates.
The Spotted Mandarin (Synchiropus picturatus) is a tiny, slow-moving fish covered in ringed spots that look like little targets. It is peaceful and reef safe, but it is a picky eater, so it only does well in the right tank.
Quick facts
- Tank size: 30 gallons or more, with lots of live rock
- Diet: live copepods (tiny bugs that grow on rock), plus frozen food if it learns to eat it
- Reef safe: yes, with corals, shrimp, and snails
- Difficulty: hard, mostly because of feeding
- Temperament: very peaceful and shy
- Adult size: about 3 inches
How to spot one
Look for a green or gray body covered in round spots. Each spot has a black center with blue and orange rings around it.
It has big eyes that move on their own, and it "hops" along rocks and sand instead of swimming in open water.
It is a cousin of the green Mandarin, which has wavy stripes instead of spots. Both need the same kind of care.
The big rule: copepods
Most Spotted Mandarins don't die from sickness. They starve. In the wild, they pick at tiny copepods all day long.
- Wait for a mature tank: add one only after your tank has run for at least 6 months
- Lots of live rock: more rock means more places for copepods to grow
- Add a refugium if you can: this is a small side tank with macroalgae where copepods can breed safely
- Seed the tank: buy bottled live copepods and add them every few weeks
Watch its belly. A round belly is good. A thin, pinched belly means it isn't getting enough food.
Tank setup
A Spotted Mandarin doesn't need a big tank to swim. It needs a big food supply.
- Size: 30 gallons is the minimum. Bigger tanks hold more copepods
- Rockwork: leave nooks and caves where it can hunt and hide
- Sand bed: a sand bottom gives it more ground to search
- Stable water: keep temperature and salinity steady
Can it eat frozen food?
Some can, but spotted ones are often harder to train than the green kind. Captive-bred fish usually learn faster, so buy one if you can find it.
- Start small: try frozen baby brine shrimp or tiny mysis
- Use a feeding dish: a small dish on the sand keeps food away from faster fish
- Ask first: before buying, ask the seller if the fish already eats frozen food
Tankmates
This fish is gentle and slow, so pick calm tankmates that won't steal its food.
- Good mates: clownfish, gobies, firefish, cardinalfish, and small peaceful wrasses
- Avoid: other copepod eaters like scooter dragonets, plus pushy fish like dottybacks
- Pairs: two males will fight. A male and female pair can work in a tank with lots of copepods
Males are easy to spot. They have a tall, spiky first fin on their back.
Want to compare it with a close cousin? Read our Red Scooter Dragonet guide or our green Mandarin guide.
Health tips
Mandarins have a thick, slimy skin coat that helps protect them from some parasites. They can still get sick, though.
- Quarantine new fish: keep them in a separate tank for a few weeks first. Our 30-day quarantine plan shows how
- Feed during quarantine: a quarantine tank has no copepods, so add live ones every day
- Check the belly often: weight loss is the first warning sign
FAQ
Can a Spotted Mandarin live in a nano tank? Only if the tank is mature, has a refugium, and you add copepods often. Under 30 gallons is risky for most people.
Is the Spotted Mandarin good for beginners? Not really. Get a few months of reef keeping done first and let your tank mature before you buy one.
Can I keep a green Mandarin and a Spotted Mandarin together? It's not a good idea. They eat the same food and can fight, so most tanks only have room for one.
Ready to add one? Check the Spotted Mandarin page on ReefBay for member photos, owner tips, and current listings, then track feedings and water tests in the ReefBay app.
