Saltcorner
By Bob Goemans
By Bob Goemans
Likely Reef Tank Suitable
Likely Fish-Only Tank Suitable
These fishes belong in the Order Perciformes and Suborder Percoidei and are members of the Family Pomacanthidae (Angelfishes) which contains about 88 species in 8 genera. They are some of the most beautiful, smart and hardy of all aquarium fishes.
All angelfishes are thought to be protogynous hermaphrodites where females change to males. They are mostly solitary swimmers, prefer shallower water in the range of 6 - 50 feet (2 - 20 m), however, a few species occur in deep water, i.e., about 150 feet (50 m). Some live in harem social groups with the male controlling overlapping territories containing one to four females. Angels experience dramatic color and pattern changes from juvenile to adult stage. Most are found in the Indo-Pacific, (Australia - 23 species; Indonesia - 21 species; New Guinea - 22 species; Philippines - 19 species; and, Taiwan - 20 species), yet about a dozen are found in the Atlantic Ocean.
Most are territorial and spend much of their time in search of food and feed upon algae, sponges, tunicates, and various other benthic items. Even though they graze on a wide variety of foodstuffs, learning just what food preference certain species have goes a long way in their maintenance. Actually, they can be broken down into three different feeding groups, i.e., zooplankton feeders, sessile invertebrate feeders, and algae and detritus feeders. For example, the genera Apolemichthys, Chaetodontoplus, Holacanthus, Pomacanthus, and Pygoplites are sessile invertebrate feeders. The Centropyge genus are mostly algae and detritus feeders. The zooplankton feeders are mostly in the Genicanthus genus.
One of the most asked questions is whether or not more than one species can be kept in the same aquarium. In small aquariums, such a practice should be avoided because they are mostly belligerent towards each other. In larger aquariums, e.g., over 100 gallons, where there are many caves and hiding places, it could house a few different angelfishes. Do not keep members of the same species together, or juveniles of the same coloration, e.g., the Koran and Emperor. Always add the least aggressive and smallest first. Wait sometime before adding the next, such as a week or two. Then add the next larger and more aggressive specimen. If there is some squabbling, try changing the way the aquascaping looks. Have fishes that differ in color patterns. Also, feed well prior to adding a new specimen and provide shelter, e.g., boulders and cave-like structures for them to investigate.
As for those in the Apolemichthys Group, they are all medium size species, and all are found in either the Indian or Pacific Oceans. Little is known about their behavioral ecology, with most solely feeding on tunicates and sponges. Nonetheless, juveniles no doubt include plant material in their diet.
For those in the Centropyge Group, most of these smaller angelfishes make very suitable aquarium specimens. They range throughout the Indian Ocean, as well as the Pacific and Atlantic Oceans. Yet, only a few of these pygmy or dwarf angelfishes are considered safe for the reef aquarium. I say safe as they sometimes become a nuisance, as they can develop a habit of nipping at the mantles of Tridacna clams and some soft corals, causing them to remain closed or at least become stressed.
This genus contains about thirty species that mainly grow between 2 to 7 inches (5 to 18 cm). They all start sexually undifferentiated, then become females, where some develop into males as they grow larger. Most are medium priced, hardy, very colorful, peaceful and/or tolerate other fishes. Many prefer rubble-like bottom areas or rocky passageways/caves. Their primary diet consists of algae and small crustaceans and they can be quite territorial, especially with members of their own species. They are susceptible to Marine Ich, e.g., Cryptocaryon/Amyloodinium, and are sensitive to copper treatments with or without formalin, as are all angelfish.
Some pygmy angelfish are collected from the Atlantic Ocean near the northern border of the Tropic of Cancer and may be accustomed to middle seventy degree water temperatures, e.g., C. argi. Therefore, check the area of origin as to water temperatures of your selected species before placing it in an aquarium environment that may be too warm. As with most other genera and species of angelfish, they prefer a diet high in algae, balanced with fortified brine shrimp, plankton, prawn, chopped clams and worms, e.g., bloodworms, tubifex, glassworms, black worms, and whiteworms. Some will also take a high quality flake food.
(The following is the results of a discussion on Centropyge species with Jim Stime, www. centropyge.net)
There are over 32 species of dwarf angels with new species being discovered all the time. Familiar examples include; Flame, Potters, Coral Beauty, Lemon Peel and the Resplendent. Dwarf angels need lots of algae to graze upon, and are very popular introductions into reef aquariums. In the wild they are often found in small shoals of females with one dominant male. If the male is lost, the dominant female simply turns into a male!
When shopping for a pygmy angel make it a point to note two things; richness of overall color, and is the fish aware of its surroundings. Select fish with deep rich color. Fish that are pale would be an indication that something is bothering the fish. Fish should react in a defensive, yet curious manner, when you approach the aquarium. They should be aware of your presence, raise their dorsal fin and exhibit a defensive posture. It is expected they will seek a hiding spot but their curiosity will cause them to peek out at you.
Pygmy angels like all other fish are subject to marine parasites such as Ick. Copper-based medications are very effective but must be used in half dose increments as Centropyge species do not tolerate immediate full dose applications.
As with other fish families it is difficult to add additional similar species when one species is already established in the aquarium, but not impossible. Many of the tanks I have owned or maintained include more than one within the same genus. Established fishes will sometimes relentlessly defend their tank choosing to viciously beat up the new addition.
In regards to creating male and female pairs I have found this to be quite easy. All Centropyge are born female. The larger or more dominant individuals will actually change sex and become males. Knowing that size is the main difference between the sexes, and not so much coloration, all one needs to do is place a small and larger version together. Within approximately 60 days either one of the two fish will have physically changed sex to accommodate each other and/or the two will have accepted their sexual role and have paired up.
Centropyge are broadcast spawners and spawning occurs at dusk or at the end of the light cycle in the aquarium. I have found by using a series of timers controlling more than one or two separate sets of lights I could create a sunset effect. The timers allowed for a consistent time frame that mimicked the rise and fall of the sun. Just as the last set of lights shown in the tank the male would begin his nightly courtship. In nature this courtship occurred with more than one female as Centropyge live in harems of six to ten individuals. The recent successes in tank spawning and raising of Centropyge specimens will ensure their continued availability, including rare specimens and eventually bring costs down.
Dwarf angels tend to accept all forms of foods. I have found that in the beginning it was good to get them feeding on frozen Mysis. This food seems to get their attention as a result of the high amount of oils and lipids it contains. Over time variety is best for any fishes. Pygmy's will nip at algae and small invertebrates, especially tanks furnished with live rock. Many hobbyists have reported that one species tends to enjoy nipping at live corals more than others. I have experienced some problems with some fish but nothing to suggest a particular species over another
Those in the Chaetodontoplus Group are comprised of medium sized species, about 14 inches in length, and all hailing from the Western Pacific Ocean, from Japan south the Australia.
Those in the Genicanthus Group are small to medium size angelfishes, mostly plankton feeders, open water swimmers, and make good reef and fish-only inhabitants. They are commonly known as swallowtails or lyretailed angelfish. They do better in an aquarium of 100 gallons and larger where there is sufficient open space to dart after plankton-like food when available. May not be safe with very small crustaceans. Males always have long fin streamer/filaments that flow from the tips of the fins. Avoid purchasing any that can't maintain their position in the water as that is an indication the swim bladder is damaged, probably during collection as they come from deeper waters.
Holacanthus Group species are constant grazers rather than consumers of large portions at single feedings. They should be fed with extreme care and particular attention paid to the quality and quantity. Frequent small feedings are better than large single feedings and sponge and some algae are of extreme importance in their diet. This species are also active swimmers and should have adequate space along with caves, tunnels, and overhanging ledges.
Those in the Paracentropyge Group are secretive in the wild and difficult to maintain in aquaria. They are thought to be sponge and tunicates eaters. They need plenty of caves and hiding places, low lighting, and no aggressive tankmates. A third member of this clan is the Peppermint Angelfish (P. boylei) and it is still not clear whether or not it's in the genus Centropyge or this one!
As for those in the Pomacanthus Group, they may be the most spectacular, probably the largest in the family, and hail from all tropical seas.
There is only one specimen in the Pygoplites Group, yet there are subtle differences in the species depending upon where it comes from. Those coming from the Pacific area generally have white on the front part of the belly. Those from the Red Sea - Indian Ocean have orange on the front belly. There is no color difference between sexes. They can be difficult to maintain, with those coming from the Red Sea reported to fare better than those from the Pacific. Juveniles prove to be quite hardy and have little color difference from an adult, however, they are somewhat more orange-yellow and have an eye spot on the rear portion of the dorsal fin.
