Breeding Clownfish - A short description

By William Berg
of Sweden, for aquaticcommunity.com
Aquarticles

Thanks to Disney's Motion Picture 'Finding Nemo,' almost everybody is familiar with clownfish.

Clownfish, or Anemonefishes, from the family Pomacentridae, are one of the easiest tropical marine aquarium fish to breed. Clownfish regularly lay eggs in aquariums. They have quite large eggs and larvae, and since the larvae easily eat cultured live foods, raising them is somewhat simpler than it is with many other marine species.

You need to get a pair if you want to breed clownfish, and that's quite interesting - believe it or not, clownfish are all born as males! When they are adults, the largest and the most dominant fish of the group will undergo a sex change and become a female. The second largest usually becomes the breeding male, while all the other fish remain juveniles and gender-neutral. If the breeding female disappears, the breeding male will change to a female, and so on. Buying an established pair may be a reasonable way to go, but it is often better to have a group of juveniles growing up together. If you choose to buy a pair you should look for a pair that goes around together. Sometimes you can be lucky enough to get a pair already spawning. Anyhow, establishing an adult pair can be a little tricky; and you need to keep your eyes on them to make sure that the female doesn't kill the male.

The next thing is to set up the tank. The tank should be large enough, approximately 200 liters for the breeding pair. It is better to keep a pair alone in an aquarium when trying to spawn clownfish.

The aquarium should be furnished with a nice anemone, a few live rocks and other rocky substances with a vertical surface, a layer of coral sand on the bottom, bright lighting, good filtration, and a protein skimmer. Your clownfish should be stress free, which means no aggressive tank mates and good water quality. As for feeding, clownfish need a mixed diet of fresh raw seafood and vegetables. A good diet includes prawns, mussels, and squid. It is best to feed small bits at regular intervals.

Spanning can begin 1 to 12 months after the fish have settled into their new home. When the fish are ready to spawn, they become very aggressive. The male clownfish will dance up and down in front of the female (also known as "clownfish waggle"). They will also start to clean their selected rock by robustly biting it. The spawning itself usually occurs in the afternoon or early evening. Once the spawning is complete (within several hours) the male takes on responsibility for attending the eggs, whereas the female acts as protector of the eggs and supervisor of her male.

Spawning is likely to occur again at intervals of 12 to 18 days. The eggs should be left in the care of the parents and not removed, unless the parents are known to be egg eaters. At first the eggs are a bright orange colour, but after several days this diminishes and the eyes appear. Hatching usually takes from 6 to 15 days, depending on temperature.

The most critical stage of the fry is the first 10 days of their larvae span. If you can get your fry to survive this period the rest of their raising should be easier.