Synchiropus in marine aquarium: how many and why?

Synchiropus in acquario marino: quanti e quali mettere?
Synchiropus splendidus – mandarinfish

We started to discuss about family of fish with the surgeonfish, today we introduce another beautiful species the Synchiropus.

Iquitos - mangimi tropicali - Colombo

This article is also available in: italiano


I’ve always loved aquariums full of fish, as if you were diving in tropical seas. I’ve always had a lot of them, the important thing is knowing which one you can insert and respecting them, obviously.

At the end, it’s all an exercise of equilibrium and proportions. A big fish in a small aquarium it’s not that nice to see and it’ll also make your aquarium appear even smaller than it is, wherever the beauty of the fish. Moreover, a lot of fish that don’t fit for their size, for example some surgeonfish, become very aggressive and can attack other fish, they can get sick frequently, infecting then the other specimens too. Then you have to consider the biological niches, for which it would be totally useless, for example, insert 20 angelfish and then complain that the noone swims in the upper part of the aquarium. Then you have to consider the colors, because some fish get very aggressive towards specimens with similar liveries. And shoal fish have to stay in shoal… and so on. But let’s continue with order.

Is there a maximum number of fish that can be kept in a marine aquarium? No, there isn’t. If you wat to obtain the maximum from your aquarium, you have to study, know and respect the fish. Choose them wisely.

The introduction it’s the same for the articles of this series


The Synchiropus are part of the family of callionoymidae, also called dragonets. They’re small fish that reach 6 or 8 cm, they’re very beautiful and colorful, and also very useful in aquarium. They swim very particularly and they’re always moving. It’s very funny watching them searching the sand and shoot it out of the gills.

Synchiropus in acquario marino: quanti e quali mettere?

They’re even more beautiful if they’re in couple: you’ll see them dancing their mating ballet… wonderful. But be careful to buy a male and a female, otherwise they easily get in cruel fights.

But let’s put some limits. As well as we said for the surgeonfish, you should study in depth every species to learn about their peculiarities, but generally you can insert one Synchiropus each 100 liters, respecting the colorations. For example, you can’t insert 3 Synchiropus splendidus, or two males. And, especially, you can’t insert any Synchiropus until a year from the starting of the aquarium, so that the fish will find the sustenance in aquarium, because they often don’t eat industrial food (can’t blame them….).

We were saying before that the Synchiropus are very useful in aquarium, because they eat the small parasites that may be in the aquarium. For example, they’re very useful against planarians, that they really like. Obviously it’s not granted, you could find the vegan Synchiropus that doesn’t like that, and that’s why sometimes it’s said that a picturatus, a marmoratus or a stellatus are better, but I think that’s always a matter of luck. The important thing to keep in mind is that they’re bottom fish and that’s where they get their sustenance, so if there isn’t enough life in the aquarium it’s like a death sentence for them.

So if you don’t have any sand, this is a fish you DON’T have to breed.

Synchiropus in acquario marino: quanti e quali mettere?
Synchiropus stellatus

One last curious thing to know about them is their night behavior. Differently from many other fish they sleep leaning on the sand, and they cover themselves with a white mucus that makes them seem dead. So don’t waoory, they’re only proctecting themselves from predators.

If you have any question we’ll be glad to answer and help you in your choice, here in the comments or on our forum.

From the same series:

We’re currently writing some articles on the various families of fish, and we we’re going to collect below each article the links of the same series. And is there a particular family that you’d like to learn more about?