Damsels in My Aquariums

First printed in TFH, August 2007

These fishes belong in the “Order Perciformes” and “Suborder Labroidei” as members of the “Family Pomacentridae” (Damselfishes) consisting of 4 subfamilies, 28 genera, and 321 species. Where reef fishes are involved, they are probably the most widespread family having species in every tropical sea in the world. It should be kept in mind that ‘Anemonefishes’ are a subfamily, i.e., Amphiprioninae, having two genera, Premnas and Amphiprion with 27 species. The other three subfamilies; Chrominae; Lepidozyginae; and, Pomacentrinae contain what aquarists generally think of as ‘damselfishes,’ with species of interest coming only the first and third subfamily.

These are mostly small fishes with what can be considered high and compressed bodies, and a small mouth. All have a continuous dorsal fin, and the males care for the eggs during the breeding cycle. Most come from shallow coastal waters, and as to their temperament, feisty would be an understatement where some of them are concerned. In fact, I always thought of some species as ‘them’ thinking they were whales, not small fish! And over the years, I’ve kept many different species, and because of that, have developed some personal preferences as to what to keep, and what I wouldn’t want to try a second time unless it had its own little world!

Most damselfishes are extremely hardy, colorful, lively, disease resistant, and inexpensive, and will eat most aquarium type foods. Those are the good points, however, unfortunately some hobbyists, especially those new to the hobby, don’t realize how territorial some species are, and/or the order in which they should be placed in the aquarium, i.e., first fish, in-between additions, or the last fish to be added.

As for my first damselfish, it was actually my first ever marine fish, and was kept in my first ever marine aquarium in the year 1956! It was netted in the reef surf areas on the western side of the Island of Okinawa, which was the South China Sea side of the Island. If memory serves me correctly, it may have been the Yellowbelly Damselfish Amblyglyphidodon leucogaster. I kept two of them by themselves in a very large globe-shaped aquarium, where they reluctantly ate goldfish flake food, the only fish food on the island, as there was no such thing as ‘marine’ fish food in those days. The aquarium contained some local beach sand, a local algae coated rock, and sometimes, strands of alga-like matter that floated in close to shore. Its water was almost entirely changed twice a week, as I lived only a short walk from the sea. And since new specimens were always readily available, I never kept my captive specimens more than a few weeks, as I did not want to lose them because of not being able to provide adequate foodstuffs. The only thing I can remember about them, was that if a placed my fingers in the bowl, they would nip at them. They were not friendly! I’ve never again kept this species, but thought I would mention here, as you might find it interesting, even though not too informative.

Since the mid 70’s, when the synthetic salt mix Instant Ocean first became available, I’ve had many different fish-only and reef aquariums. As mentioned above, kept many different types of damselfish in many of those aquariums, and because of that, have over the years developed some personal preferences as to what can be called favorites, and not so favorites. And since there’s no way I can recall aquarium by aquarium what was in each when it comes to damselfish, the best way for me to write this article would be to discuss those that have become my favorites, and some that require much more forethought before placing them in another aquarium.

My top choices are two Chromis species in the Subfamily Chrominae, as they make wonderful peaceful tankmates, and can be kept in small groups, where they often school, i.e., swimming together as a coordinated group. The first is the Green/Blue Green Chromis, Chromis viridis. It hails from the Tropical West Pacific and attains about 2.5 inches (6.5 cm) in the wild. Its suitable for both fish-only and reef aquaria, and I’ve always tried to keep at least 6 of them, if the aquarium was between 50 – 100 gallons. Sometimes, in larger aquarium, I’ve maintained as many as 18, and have always tried to buy the entire group at one time so as to try and maintain a grouping of equal size. I should note, I’ve found them sensitive to shipping stresses, with many perishing within a week of arrival in many shops. Therefore, when shopping for these fish, if the dealer had just received them, I would ask the shop to save me ‘X’ number and I would be back in a week to get them. If they were already in the shop for a while, I would want to know when they arrived, and simply add the necessary number of days, then return to get them. This has greatly cut down on losses, but I’ve also found them to be somewhat sensitive to the trip home from the local shop, therefore always spent more time on acclimating them than I would with most other fish. Once established, they always proved to be very hardy, eager eaters, and never bothered their tankmates or invertebrates of any kind in the aquarium. And as a bonus, they are mid-level to high swimmers, always active and staying in view. They make a good beginners fish, as they are also very inexpensive.

Before I mention my second favorite, I should note there is a look-alike, which is C. atripectoralis. In fact, it’s more widely distributed and occurs throughout the Tropical Indo-Pacific and is often misidentified as C. viridis. Its popular name is the Black-axil Chromis, and is best identified by its black pectoral axil, which C. viridis does not have. It’s about an inch (2.5 cm) larger, with similar traits, except this species is considered even more peaceful than C. viridis!

My second favorite, Chromis cyaneus, is often called the Reef Chromis or Blue Chromis, and sometimes, the Blue Forked–tail Chromis. These hail from the Tropical West Atlantic and Caribbean, where they are found in large aggregations above coral heads. They tend to get slightly larger than my first favorite, as they attain about 4 inches (10 cm) in the wild. Even though these two ‘favorites’ have similar traits, these tend to be a bit more scrappier, yet not to the point where they stress their tankmates or bother invertebrates. Purchasing juveniles seems to be the way to go with this species, as they tend to be more social and amenable to their surroundings. They also should be kept in small groups, and in my opinion, need to be carefully acclimated before adding them to your aquarium. As for the diet of the above-mentioned species, meaty foods, such as mysis, brine shrimp, Cyclop-eeze, and flake foods enhanced with various vitamin and mineral additives, fed twice a day will keep them healthy and happy. And one further important aspect where these two favorites are concerned; they can be added to any style aquarium at whatever period in time, as they will not think or act like they own the aquarium. They make peaceful additions at any time in the time span of the aquarium.

Staying in the Subfamily Chrominae, there are a few that I’ve had in the Genus Dascyllus, and would think long and hard about ever keeping them again. Not because they were expensive or not hardy, as just the opposite is true. In fact, there’s probably not a shop that doesn’t have these fish for sale in their tanks. The first was D. aruanus, which is generally called the Humbug or Black and White Damselfish. It hails from the Western and Central Pacific, where it’s found in shoals around corals heads in lagoons, and attains a 4 inch (10 cm) length. As juveniles, they are cute and can be kept in groups. In fact, they are so hardy they can be used to cycle an aquarium. But when they get larger, they will fight among themselves and pick on tankmates unless they are much bigger and more aggressive, e.g., Moray eels, and Triggerfishes. And even though they will not harm sessile invertebrates and are easy to feed, in a mixed-company aquarium, whether they were first or last to be added, they think themselves whales and that they own the aquarium. Not only can they cause their tankmates much stress, they can cause gray hair in aquarists!

The second in this genus was D. melanurus, the Blacktail or Striped Damselfish. It hails from the Central Indo-Pacific, and generally inhabits lagoons and bays. It’s often confused with the above-mentioned species; however, this species has four black bands, whereas the above species has three. It gets about 3 inches (8 cm), yet has the same traits. The same is true for the third species in this genus, the Threespot or Domino Damselfish, D. trimaculatus, which is found throughout the Tropical Pacific and Central Indo-Pacific. As for these three Dascyllus species, they must be recognized for what they are, inexpensive, hardy, easy to feed, yet should ‘only’ be kept with more aggressive fishes, as they become ‘terrors’ as they grow to maturity.

Moving into the Subfamily Pomacentrinae, and keeping with the few ‘terror’ subjects mentioned above, I want to mention one species, Microspathodon chrysurus, the Jewel Damselfish, which hails from the Tropical West Atlantic from Florida to Brazil and gets to about 7 inches (18 cm) in the wild. I’ve had only one, which probably was one too many. As a juvenile, this is a very pretty deep blue fish with iridescent blue spots on it body, hence its name. As it grows larger, the spots become smaller and the body coloration changes to a yellowish-brown. Not only does it lose its pretty appearance, it will occasionally feed upon coral polyps, and that’s besides it being a terror in mixed company aquariums where its inhabitants are more mild mannered. Forewarned is forearmed.

When it comes to the Genus Chrysiptera, there are several good choices, and I’ve had very good success with them. One of the most commonly available species is the Yellowtail Blue Damselfish, C. parasema. It comes from the Central Indo-Pacific where it inhabits, in large numbers, areas around dense corals growths and gets to about 3 inches (7.5 cm) in length. It’s another readily available species in the trade, and always inexpensive considering its electric blue body and yellow tail. As with most damselfish it thrives on meaty foods, e.g., mysis shrimp, brine shrimp, shredded marine fish or crustacean flesh, Cyclop-eeze, and enriched flake foods. Besides its beauty and small size, this is one of the more peaceful species in this genus and can be kept in small groups in mixed company aquariums, and will not harm invertebrates. It also provides some algae grazing, as ‘green’ foodstuffs are also on its menu. As for additions to an up and running tank, I’ve added this species at different timeframes, yet found it better to add them after the majority of my other fish were in the tank, or as the last members to be added. I’ve found those first in the tank to become a little feisty in defending their chosen areas, whereas, those added somewhere down the line to better coexist with existing tankmates and ‘their’ areas.

Before I move onto another favorite in the Chrysiptera genus, there’s a look-alike Yellowtail Blue Damselfish that you should be aware of because it’s not as peaceful and that’s Pomacentrus philippinus. It hails from the Western Pacific and also the Central Indo-Pacific. Its blue coloration is much darker, has a very slight tinge of yellow in its pectoral and pelvic fin edges, and the yellow in its tail is somewhat dull looking. I’ve seen both in shops equally labeled as Yellowtail Damselfish, and that concerns me, as this species is aggressive towards smaller tankmates and/or more docile members. And once in the tank, good luck on getting it back out! Again, forewarned is forearmed.

My other favorite in the Chrysiptera genus, and one I liked very much, C. cyanea, is known under a few common names, e.g., Orangetail Damselfish, Blue Devil, or Blue Damselfish. There’s been some confusion in the past in identifying this species, as they hail from a wide area, i.e., Central Indo-Pacific and the Indo-West Pacific where they take on slightly different body marking and coloration. The female, which has a blue colored body, always has a black spot at the base of the rear soft area of the dorsal fin and always has a clear tail. The males, with those coming from the Pacific and Great Barrier Reef, are a bright blue with some yellow in the mouth area and under the front portion of the head, yellow pelvic fins, and mostly a yellowish-orange tail. Those from the Central Indo-Pacific are similar except they have mostly blue tails. In fact, I’ve seen shops misidentifying the species and housing a tank full of Orange-tailed specimens as ‘Orangetailed Damselfish. When asked, toque in cheek, which ones were the males or females, I was told only they knew. In fact, another tank in the same shop had the females mixed with what may have been C. springeri, common in the Philippines and an all blue damselfish of similar size. I did inform the shop owner of the needed correction. This is an excellent aquarium fish, and besides being quite hardy, will take the same foodstuffs mentioned above and not harm invertebrates. Again, I suggest getting juveniles, as large males can be a little feisty, and I’ve found it best to add them as the last fish in the aquarium.

I’ve also kept two other quite peaceful damsels in the genus Chrysiptera, e.g., C. hemicyanea (Azure Demoiselle), and more recently, C. starcki (Starck’s Demoiselle). They both made good reef aquarium additions, and were added at various times during the history of those aquariums. Both did well on the foods mentioned above.

And I could go on about some other damselfish I’ve kept over the past thirty years, but want to mention some I would not consider trying unless you were fully aware of their bad disposition, and those are some in the Genus Neoglyphidodon. I single these out because some of its members show up in the trade as very pretty and tempting juveniles, e.g., N. crossi; N. nigroris; and, N. oxyodon, but become holy terrors as they mature, besides becoming quite drab in coloration. If you want to keep these members, then do so knowing their temperament and forthcoming coloration changes, and do so in an aquarium where its tankmates are more aggressive, such as with moray eels and triggerfish.

In closing, there are many different damselfish to chose from with differing personalities ranging from very peaceful to terrors! Make sure you properly identify your selection prior to bringing it home and placing in your aquarium.

Kingdom: Animalia

Phylum: Chordata

Class: Actinopterygii

Order: Perciformes

Suborder: Labroidei

Family: Pomacentridae

Subfamily: Amphiprioninae

Genera Premnas; Amphiprion

Subfamily: Chrominae

Genera Acanthochromis; Azurina; Chromis; Dascyllus

Subfamily: Lepidozyginae

Genus Lepidozygus

Subfamily: Pomacentrinae

Genera Abudefduf; Amblyglyphidodon; Amblypomacentrus; Cheiloprion; Chrysiptera; Dischistodus; Hemiglyphidodon; Hypsypops; Mecaenichthys; Microspathodon; Neoglyphidodon; Neopomacentrus; Nexilosus; Parma; Plectroglyphidodon; Pomacentrus; Pomachromis; Pristotis; Similiparma; Stegastes; Teixeirichthys