Clownfish are classified to the family Pomacentridae. The clownfish is among a group of species commonly referred to as damselfish. There are 28 recognized species of clownfish. Of those, 27 belong to the genus Amphiprion. Clownfish are native to both the Indian and Pacific Oceans. Their natural habitat includes the Great Barrier Reef and the Red Sea.
The color palette varies among clownfish depending on the species. They can be found in orange, reddish orange, maroon, yellow or black. Most species have the characteristic white bars with black trimming on their bodies for which they are named. These white and black stripes contrasting against the fish’s body color make them look as if they are wearing a clown costume. Clownfish grow from 4-6 inches depending on the species. Their lifespan ranges from 3-6 years.
Clown fish are well known for the symbiotic mutualism they share with the sea anemone. The co-evolution of these two animals makes for one of the most interesting symbiotic relationships found in nature. Sea anemones are highly toxic to most marine life. This exotic creature paralyzes its prey with powerful neurotoxins. It then uses it tentacles to draw the prey into its gastrovascular cavity for digestion. This singular cavity functions as both a mouth and an anus. The digestive process results in semi-digested matter floating around the immediate vicinity of the anemone. Clownfish ingests this matter as a source of protein. They then excrete fecal matter which is an additional source of protein for the anemone.
Clownfish have a mucus membrane surrounding their bodies that acts as a natural barrier against the anemone’s poisonous nematocysts. Scientific experimentation has resulted in the death of clownfishes exposed to these neurotoxins after being stripped of their protective mucus. This mucus allows the clownfish to seek shelter from predation within the protection of the anemone’s tentacles. It is common for the clownfish to remain within 2-4 inches of its host for its entire lifetime. This symbiosis has lead to clownfish being commonly called an anemonefish.
Clownfish are hardy and docile creatures. They make an excellent choice for amateur aquarists. They are also the perfect addition to a marine reef tank. Maintaining sea anemones presents more of a challenge. Fortunately for the beginner, clownfish can be kept without their natural host animals present. Just make sure to provide them with adequate hiding places and avoid mixing them with more aggressive species and you will be fine. Once you become more experienced you can choose to add an anemone to your aquarium. Make sure to check for compatibility with your local fish store or online retailer. Individual species of clownfish are compatible with different sea anemones (see also table below).
Despite their demean nature, clownfish will exhibit territorial behavior toward other clownfish, especially clownfish of the same species. It is best to keep a single clownfish or a pair.
Clownfish have been commercially bred in captivity. When purchasing any fish that can be bred in captivity you want to buy captive-born rather than a fish caught in the wild. You will have a happy, healthier fish that is much more likely to acclimate to its new surroundings. And tank bred fish are generally more disease resistant than their wild counterparts.
Clownfish are omnivorous. A clownfish raised without the presence of a sea anemone can be fed vitamin enriched brine shrimp, or zooplankton in combination with marine frozen foods formulated for omnivores.
Unlike most hermaphroditic fish species clownfish are sequential hermaphrodites. All clownfish are born as males as opposed to protogyny hermaphrodites who are always born as females. If there are two clownfish in an aquarium together the larger more dominant of the two will transform into a female.
You will want to use a breeding tank if you are attempting to breed clownfish couple in captivity. Place a piece of pvc pipe in the bottom of your aquarium floor to be used as a breeding chamber. Eggs will be deposited either on the bottom of the pipe or on the surface of a flat rock near by. The fry will hatch 6-10 days later.
Newly hatched fry are very small. They should be fed rotifers until they mature. Once they get a little larger they can be fed newly hatched brine shrimp or powdered dry food.
Author: Exotic-Aquariums (no longer online)
Types of Anemones for Anemone fish
Not all anemones are suitable for all Anemonefish. Below is a table of possible combinations. Please note: this list is not complete and does not guarantee that a combination will always work. Some Anemonefish use an anemone that would not normally form a combination, so your own research can do no harm!