Damselfish are very common in the warm waters of the Atlantic Ocean and are another popular category of fish aquarists prefer for their reef tanks. They tend to swim freely out in the open making them visible most of the time which is desirable when many other fish are quite shy. They are a great beginner fish and are often used to "break-in" new aquariums to establish the nitrification cycle because they are very hardy and relatively inexpensive.
Damselfish belong to the Pomacentridae family, of which there is over 250 species. They are very common in the warm waters of the Atlantic Ocean and most should be kept in tanks of at least 20 gallons. Available in a variety of vibrant colors and will eat any meaty seafood, pellet or flakes. Damsels are reef safe, coral safe, and invertebrate safe. These great characteristics, make them highly desirable additions to a reef tank.
But beware, some of these wonderful qualities are not always the case with each species. Damselfish can often be aggressive to other smaller, more passive fish, so be careful. They are known to be territorial and will defend their area in the aquarium, making them great tank mates for larger saltwater fish.
Though quite a few tend to stay around two to three inches, there are some that can get quite large, like the Garibaldi that is said to reach up to 15 inches (38 cm) in length. They are best keep as a single fish unless the tank has many hiding places or is larger than 50 gallons.
Some of the most popular in the saltwater aquarium hobby are the Neon Damselfish, Domino Damselfish, Green Chromis Damselfish, Jewel Damselfish, Sunshine Chromis Damselfish, and Bali Golden Yellow Belly Damselfish.