Fishes for the Beginning Marine Aquarist

If you’re planning on setting up a saltwater aquarium, or are actually in the process of doing so, you should give careful consideration to the fish you intend to keep. It is essential to carefully select species that are compatible. This is the only way to avoid difficulties with aggression among the tank’s inhabitants, outbreaks of disease and the inability to provide proper nutrition.

Your initial concern should be with the basic disposition of the fish you are considering. Marine community aquariums tend to fall into categories based on the temperaments of the fish, which can range from passive to very aggressive. A passive fish community would be made up of species that are relatively peaceful in general-if not among themselves, at least toward members of different species. Typical choices for a peaceful community would include most cardinalfishes, green chormis damselfish, butterflyfishes, gobies, blennies, tilefishes, and certain wrasses.

A community setup that contains somewhat more aggressive fish would consist of species that are too intolerant for the peaceful community. Among the choices for this type of tank are dottybacks, angelfishes, certain hawkfishes, most damselfishes, sand perch, surgeonfishes, and pufferfishes are fishes for the beginning marine aquarist.

At the other end of the behavior spectrum are the species best suited for an aggressive community tank. Possible choices would include the eels, frogfishes, lionfishes and other scorpionfishes, groupers, some of the larger damselfishes and dottybacks, triggerfishes and porcupinefishes. Some of these fish (frogfishes, lionfishes) are included here not because they are agressive but rather because they will prey on the smaller fish in the less aggressive communities.

By avoiding the mixing of species that vary significantly in disposition, you are more likely to avoid problems with disease, which often gain a foothold when fish are under stress. Chronic aggression and harassment simply reduce the ability of a fish’s immune system to resist disease-causing organisms over the long term.

In addition to the factors noted above, you want to avoid species that have unsual or unique food requirements. The fish listed below are able to thrive on the typical foods that most marne aquarists can easily obtain. The healt and longevity of marine fish depend on both a proper aquatic environment and a balanced diet that supplies complete nutrition, including trace elements. Fish, unlike some invertebrate, obtain their trace elements from their food, not from the water.

Muraenidae and Ophichthidae

Moray and snake eels (Muraenidae and Ophichthidae)

The Fishes

Both groups are fascinating additions to the predatory or aggressive community aquarium, and the moray eels are smoe of the hardiest fish available to the hobbyist. In general, snake eels tend to be more difficult to feed than morays. And, unlike morays which spend most of their time hiding in reef interstices, snakes eels bury themselves under the sand. Therefore, they should be provided with plenty of substrate in which to hide. Snake eels feed almost exclusively on crustaceans, while man morays also include fish in their diets.

Morays have fistensible jaws that enable them to eat amazingly large prey items – be aware of this when selecting potential tankmates for your eel. These animals are also proficient escape artists, often exiting the aquarium out of the smallest openings in the plastic backstrip.

The snowflake moray (Echidnanebulosa) is a good choice for the novice. However, it may eat ornamental shirmp and may snap indiscriminately at your fish during feeding sessions. It should be fed a varied diet consisting primarily of chopped table shrimp. Avoid the zebra moray (Gymnomuraena zebra), the ribbon eels (Rhinomuraena spp.), the banded snake eell (Myrichthys colubrinus) and the Hawaiian leopard moray (Uropterygius tigrinus), because they are extremely difficult to feed in captivity.

Frogfishes (Antennaridae)

Frogfishes (Antennaridae)

These are great fish for a species tank – a tnak wher only one type of fish is kept – or some predatory or aggressive community settings. They do well in smaller tanks and are fascinating to watch. They have a modified first dorsal spine that they wave aorund to lure fish to within striking range. If kept with other fish, their tankmates should be considerably larger than they are, especially if they are alongate in shape (e.g., wrasses).

Frogfish have a highly expandable stomach and can eat prey that is longer than they are. It is important that you do not feed your frogfish oversized prey items. If you do the frogfish may have a problem digesting the meal and the resulting gases poduced in the digestive tract may cause the fish to bloat, float and die.

Frogfishes will sometimes fill their stomachs with air when lifted from the water and may have difficulty expelling it. Therefore, when capturing a frogfish, it is important that the fish is herded into a bag or a plastic specimen container, and not lifted by net out of the water and placed in the bag. Frogfish can be kept together, but if there is a great size disparity between individuals, one may eat the other !

Avoid placing them in with triggerfishes, larger angelfishes, pufferfishes, or porcupinefishes. These fish have a tendency to bite and maim frogfishes, because of the frogfish’s incredible ability to mimic the invertebrate encrusted substrate. It may be necessary to entice your frogfish to food with live food, but try and switch them over to fresh, dead seafoods (e.g., table shrimp, strips of silverside) as son as possible.

Squirrelfishes (Holocentridae)

These are nocturnal fishes, most of which are red in color and have enlarged eyes. Numerous ledges and caves should be provided for refuge – they will spend mosts of the day – light hours peering out form these hiding places.  Squirrelfishes may be aggressive towar fish that try to enter their shelter sites, those that are introduced into the tank after them, or those that are much smaller than they are. Squirrelfishes are usually not finicky feeders and small fish. They communicate by making audible clicking or grunting sounds, which usually occurs when the fish is agitated.

Scorpionfishes (Scorpaenidae)

Scorpionfishes (Scorpaenidae)

This family of fishes includes one of the most popular groups of marine fish, the lionfishes. Scorpionfishes are predator that prey on crustaceans and small fish. They should therefore, only be kept with fish that are too large to fit in their capacious mouths. More than one specimen can be kept in the same tank, because they are rarely aggressive towar each other in the aquarium.

Extrem caution should be taken when netting a scorpionfish, or when cleaning its tank. The dorsal spines are venomous. Some lionfish have a habit of sitting motionless under a ledge or against the backside of a piece of coral and may go unnoticed by the unobservant aquarist. Although stings are rarely fatal, they can be extremleyu painful and may require medical attention.

Do not be alarmed if your scorpionfish looks as though it is “shedding” layers of slime. Many of these fish will occasionally shed the outer layer of their skin in order to get rid of any algae or invertbates that may be growing on it. It may be necessary to feed live foods to new specimens, but they can usually be taught to eat strips of silverside from a feeding stick – a piece of rigid air-line tubing with a sharpened end – or to take prepared foods carried by water currents.

Dottybacks (Pseudochromidae)

The dottybacks are hardly fish that are often very colorful. Smaller species of the genus Pseudochromis can be aggressive, especially to smaller, passive species like grammas, gobies, dart gobies, and the small wrasses, as well as to other dottybacks. Only one speciment of dottyback should be kept per tank, unless the tank is very large and plenty of hiding places can be provided. Dottybacks are prone to dramatic color loss if a varied diet is not provided.

The most desirable dottyback is the orchid dottyback (Pseudochromis fridmani). The species, which is an intense magenta in color, is relatively docile, hardy, and will maintain its coloration into adulthood. Because it is limited in distribution to parts of the Red Sea, it usually commands a high price. The neon dottyback (P.aldabraensis) is also beautiful , hardy and expensive, and is as aggressive as it is robust. It is a good fish for the novice because of its resistance to poor environmental conditions. However, it should onlu be kept with other aggressive fish. Similarly, members of the genus Ogilbyina and Labracinus (e.g., the Australian dottyback, the sailfin dottyback, the Dampiera) are very belligerent and should only be kept with fish of similiar disposition. They are also extremely rugged, often surviving disease epidemics and bad water conditions.

Grammas (Grammidae)

There are three grammas that sometimes appear in aquarium stores, but only one shows up regularly. The royal gramma (Gramma loreto) has long been a favorite among hobbysts throughout Nort America. It is hardy, colorful, and relatively peaceful. More than one individual can be kept in a medium-size tank, as long as plenty of hiding places are provided. Although it may lose its original luster, even faded specimens are quite attractive.

The blackcap basslet (G. melacara) also make its way into aquarium shops occasionally. It is very similiar in behavior to the royal gramma, but occurs in deeper water (usually greater than 70 feet) and, is more to suffer from problems associated with decompression. Avoid specimens that swim wtih their tails up and that have a problem staying motionless in the water column.

Sea bettas and Assessors (Plesiopidae). Their are two species of sea bettas in the genus Calloplesiops, both of which are occasionally available to hobbyists. The most common is the comet (Calloplesiops altivelis). This fish is extremely disease resistant, is not overly sensitive to deteriorating water quality, and is not aggressive. However, the comet may consume your ornamental shrimp and is known to be secretive, spending most of its time hiding in reef crevices and caves. In a fish-only tank it is important that you make a special effort to feed your comet, Initially, it may be necessary to feed live foods in order to catalyze a feeding response, but with time itu should start taking food placed in, and taken by, a strong current.

The argus sea betta (C. argus) is occasionally available. This impressive species has a greater number of smaller dots on its body and fins than to comet, and has larger pelvic fins.

The smaller assessors are also great fish for the beginner. The blue assessor (Assesor macneilli) is a royal blue in color, while the yellow assessor (A. flavissimus) is yellowfish orange with bright orange trim on its fins. Both og these species are usually observed in the wild, in groups, swimming upside down under ledges and in caves. Both are sturdy aquarium fish, which are not aggressive toward other fish, and their small size (under 3 inches) makes them ideal candidates for smaller aquaria. They can be kept in small groups in a medium-size tank if plenty of hirouding places are provided and if there is some size disparity between specimens.

Cardinalfishes (Apogonidae)

Cardinalfishes (Apogonidae)

Althought this is a very large family, with over 170 members, relatively few are available in the marine aquarium trade. Most appear to be ideally suited for the home aquarium and are very affordable. The best choice for the beginner is the pajama cardinal (Sphaeramia nematoptera). This species is extremely hardy and nonaggressive and can even be kept in small groups. Many cardinalfishes are nocturnal, spending the daylight hours hiding in crevices. The pajama cardinalfish, however, is almost always in plain view. It usually hangs motionless over the aquarium decor. The orangeline cardinalfishes (Apogon cyanosoma) and the flame cardinalfish (A. maculatus) are also good fish for the beginner.

Butterflyfish  (Chaetodontidae)

Butterflyfish (Chaetodontidae)

Most of the butterflyfishes are not suitable for the beginner because of their specialized diets and sensitivity to disease. However,ol there are several species that are exceptions to this rule. The easiest butterflyfish to maintain in captivity are the pyramid butterfly (Hemitaurichthys polylepis), the lemon or millet seed butterfly lta(Chaetodon milliaris), and Klein’s butterfly (C. kleini).

In the wild these three butterflyfish feed heavily on zooplankton, although the latter species also eats soft coral polyps. In captivity they will eat most fresh or frozen foods. It is important that they be provided with a varied diet and that they be fed at least twice, and preferrably three times, a day. These fish are not aggressive and are sensitive to being bulled.

Other butterflyfish recommended for the beginner include the threadfin or auriga butterfly (C. auriga), the raccon butterfly (C. lunula), the blackback butterfly (C. melannotus), and the vagabond butterfly (C. vagabundus). Never purchase species that are obligate coral feeders, such as the Arabian butterfly (C. baronessa), the larvatus butterfly (C. larvatus), the ornate butterfly (C. ornatissimus), or the melon butterfly (C. trifasciatus). These species have little, if any, chance if surviving in captivity.

Angelfishes (Pomacanthidae)

Angelfishes (Pomacanthidae)

This family contains some of the most stunning of all the marine fishes, although most species are onlu suitable for the more experienced fishkeeper. Some of the pygmy angelfishes, however, can be recommended for the novice aquarist. These include the coral beauty (Centropyge bispinosus), the cherub fish (C. argi), the flame angelfish (C. loriculus), the keyhole angel (C. tibicin), and the rusty angelfish (C. ferrugatus). These pygmy angelfishes do not exceed 6 inches in total length and can be kept in smaller aquaria. They feed primarily on algae and detritus in the wild and adapt quite nicely to aquarium diets.

A lot of the larger angels feed almost exclusively on sponges and suffer the consequences as a result of the lack of this component in their captive diets. These larger fish also require a lot of space in order to survive. The koran angelfish (Pomacanthus semicirculatus), the passer or king angelfish (Holacanthus passer), the queen angelfish (H. ciliaris), the blue angelfish (H. bermudensis), and the Indian Ocean yellowtail angel (Apolemichthys xanthurus) are all larger species that will often adapt to life in a larger aquarium. It is best to buy smaller specimens because they seem to handle the shipping process better and are easier to acclimate, Angelfishes should be given a varied diet, that includes leaf lettuce that has been steamed or frozen.

Damselfishes (Pomacentridae)

The damselfishes are the most ubiquitous reef fish in any aquarium shop. This is because most of them are hardym inexpensive, and very colorful. However, most of them are highly territorial. This can bi a big problem if they are the first fish in a small or medium-size tank. They will claim the entire aquarium as their terittority, making life introduced later on.

Some are well mannered as juveniles, but as they increase in size, the desire to destroy their tankmates also increases ! Members of the genus Dascyllus (e.g., the domino and striped damsels) make this transition from “cute” little fish to “murderous” big fish.

Watch out for the black and gold damselfish (Paraglyphidodon nigroris) and the bluefin damsel (P. melas) ! Both of these have a tendency to change color – from colorful to drab – and personalities, as they mature.

Two common damsel that do well in most passive community settings are the yellowtail blue (Chrysiptera parasema) and the green chromis (Crhromis viridis). The green chromis is very docile and can be kept in schools.

Another group of damselfishes that make good aquarium residents for the beginning aquarist are the anemonefishes. These fish do best when kept alone or in known male-female pairs. Although they can be kept without an anemone, it is always fun to watch them interact with their invertebrate host. Recommended species include the spinecheeked or maroon clown (Premnas biaculeatus), the tomato clown (Amphiprion frenatus), the pink skunk clown (A. perideraion), the false percula clown (A. ocellaris), and Clark’s anemonefish (A. clarkii).

It is best to purchase only those anemonefishes that have been in the dealer’s tank for at least a week or more. This way the chances of your receiving only healthy specimens is greatly increased.

Next month we will look at the remaining families of marine fish that you might want to consider for your saltwater aquarium. In the meantime, you might spend sometime reading more about the species I have suggested thus far.