The humbug damselfish (Dascyllus aruanus) goes by many other names, such as three stripe damselfish, humbug dascyllus, or black and white damselfish. The damselfish in the above photo appears blue and black instead of black and white due to the aquarium lighting. It belongs to the family Pomacentridae.
Like all damselfish, humbug damselfish are good fish for beginning saltwater aquarists. They tend to tolerate fluctuating water conditions better than a lot of other saltwater fish.
It should be noted that humbug damselfish can be very territorial in the aquarium, especially as they get older. You should either keep only 1 humbug damselfish or a small group of 4 to 8 (meaning if you get more than one you must get at least 4 of them). The dominant humbug damselfish may bully the others, and if you have several in your tank, then no one fish will have to take the brunt of the aggressive behavior of the dominant humbug.
It is also recommended that you add all of the other fish to your tank first and the humbug damsels last. This will help to minimize their aggressive behavior. If you add them first then they will begin to think they own the aquarium and then they won't tolerate new fish that are added to the tank. You should also provide lots of rockwork for hiding places.
Humbug damsels will also bully peaceful, timid tankmates, as well as other species of damselfish. You should keep this in mind when choosing fish for your community saltwater aquarium. Humbug damsels are very aggressive fish despite their small size. They only reach an adult size of 3-4 inches (7.6-10 cm).
Humbug damselfish are found in shallow waters in the Indo-Pacific. They are good fish for reef tanks. In their natural habitat they live around coral colonies and so they will enjoy having coral in their tank.
They are omnivores, eating both plant-based and meaty foods. They often feed on algae. You can give them frozen food for marine fish, vitamin enriched brine shrimp, and mysid shrimp. They will often eat dried flakes and pellets as well.
Like many other reef fish, humbug damsels have the ability to change their sex.
Humbug damsels can be purchased for about $5.