Selecting Your Saltwater Fish: As an illustration, let's assume that you are setting up a 30-gallon tank and from that point of view we'll consider several possibilities, always keeping in mind the habitat requirements and behavior patterns of the fish.
Marine fish occupy all levels of the habitat from open water, coral reef, grass flats, to the bottom substrate. When considering habitats of marine tropicals, generally, jawfish are substrate dwellers, blennies and grammas are rock dwellers, angelfish and butterflyfish are open water fish that "hole up" in the rocks and coral at night, and damsel fish occupy whole territories of rock, water, and substrate!
Behavior patterns and habitat requirements are generally the same for both Atlantic and Pacific species of the same families. Pacific fish, however, do better at a lower salinity and a lower temperature than Atlantic species. They are also considered by some people to be far more colorful than their Atlantic counterparts. Because some of the marine tropicals such as butterfly fish, rock beauties, and tangs have very specific dietary requirements, I do not recommend their purchase if you cannot provide the proper foods. When you begin choosing fish, make decisions slowly. There are lots of available choices even if this is your first tank and if you proceed slowly, it is hard to fail.
One of the most popular groups of aquarium fish are the angelfish. If you decide to put some angelfish in your tank - and they are an excellent choice for beginners - be sure there is a definite size difference between species. The most docile should be the largest and the most aggressive the smallest. Also, if you are going to have more than one of any species (example 3 pigmy angelfish, Centropygi argi), they should all be added at the same time because certain species are aggressive especially towards each other. Keep in mind some of the angelfish are cleaners in their juvenile stages and other species grow to be quite large as adults. Angelfish habitat requirements and behavior patterns are similar. They "hole-up" at night and during the day spend their time in front of the rocks and corals. They like frozen brine shrimp, dried foods and live green algae - basically an easy fish to g,et to feed. I would not suggest more than 3 angelfish in a 30-gallon community aquarium.
Butterfly fishes are generally less hardy and more difficult to maintain than the angel fishes. Some of the Pacific species must feed on polyps from specific types of coral in order to survive, while others will eat anything you put in the aquarium. Usually butterfly fishes are not as aggressive as angelfishes and thus should be the larger when both are in the same aquarium. Three of the six species available from the Atlantic that do very well in the home aquariums. They are the Atlantic long nose (Prognathodes aculeatus), the reef (Chaetodon sendentarius), and the banner (~. aya). The spot fin (~. ocellatus), banded (C. striatus), and four-eye (~. capistratus) butterfly fishes are more difficult and sometimes never start feeding well, if at all. If you have a butterflyfish that is not feeding you might try using an old bleached piece of coral (rose coral works very well), and mash a small piece of raw shrimp into the coral and place that in the tank. Don't put too much shrimp on the coral as it does spoil and can foul the tank. If the butterflyfish starts to feed you can increase the size of the shrimp to match the food requirements of the fish.
Another method to stimulate feeding is to add live brine shrimp (Artemis salina) or frozen brine shrimp thawed and soaked in an appetite stimulant. Up to three butterflyfish can be considered for a 30 gallon aquarium. Other options for middle tank dwellers (besides angelfish and butterfly fish) that should be considered are hogfish, tangs, cardinalfish, squirrelfish, and big eyes. These latter three are reef dwellers that live under rock ledges during the day and come out at night. As a result, they do not do well in brightly lit areas but are good fish in home aquariums where ledges are provided. Tangs are herbivores in their natural habitat. This means they are plant eaters and require algae in large amounts to be happy and to do well. They will eat dry foods and frozen brine but need algae to maintain color and proper diet.
Hogfish, wrasses, small sea basses and groupers (Serranids) all are good feeders and are very hardy. Keep in mind, as serranids get bigger, they do develop a taste for smaller fish! One to three of any of the many options from the middle tank dweller will enhance a 30-gallon aquarium, especially since they are so brightly colored. Fish living on the bottom are probably the most popular; good choices would be found among the various species of jawfish and worm gobies. A 30-gallon tank can handle up to six. Jawfish are a good choice, add activity to any tank, have been known to spawn in a community tank, and are all hardy and good feeders. The most important consideration for jawfish is the bottom substrate. Jawfish and worm gobies need shells or coral pieces to structure holes in the bottom of the tank. If you use a "soft" media, such as the finely crushed coral sold commercially, then you must provide them with some decorative clam shells or flat rocks to hide under. If jawfish are unhappy with their "home" they will go to the jawfish, worm gobies, or other bottom dwellers in your system. crabs and brittle starfish instead. surface and look for a way out of the tank. They usually succeed, too - much to your distress!
Bottom dwellers are also notorious for rearranging an aquarium, moving bottom media, shells, plants, etc., to suit their desires. If you don't want your aquarium rearranged regularly, do not put Use hermit Rock dwellers are also good and possibilities include neon gobies, other gobies, basslets, clinnids, hawkfish, and blennies. The neon goby is a cleaner fish and a pair can be both attractive and functional. They will establish a cleaning station, much as in nature, and have been known to spawn in a closed system. Another choice is the basslets, including the royal grammas (Gramma loreto) and the blackcap basslets (G. melacara). 16 These are aggressive fish, especially among their own kind. If you are going to put in more than one gramma or blackcap basslet they must all be introduced at the same time. Once established, the first arrivals will kill any new basslets introduced. Grammas live under ledges in your tank and it is not unusual to see them swimming upside-down. Other rock dweller choices can be made as much on color as on species. Blennies and jawfish are incompatible in the same aquarium and may create some problems, so you may want to consider one of the other rock dweller species if you intend to keep jawfish.
Damsel fish are the one group of fishes that will live, grow, and spawn in nearly anyone's tank. They are very hardy, almost indestructible and do well in any system. If there is a drawback, it is that they are aggressive and extremely territorial. You must remember to leave room for them. If you plan to introduce damsels, remember that each fish requires considerable bottom and rock area as a part of its habitat. Plan for it. Some of the least aggressive damsels are the saffron (Eupomacentrus planifrons), honey gregory (!. mellis), the salt and pepper (E. partitus), and blue and green reefs (Chromis sp.). If you add damsels, be certain they are the smallest fish in the tank. You needn't worry about their size. Damsels are very competent at taking care of themselves even with fish ten times their size.
Invertebrates can also be added especially the hardy species. Some choices include banded coral shrimp, sea .anemones, brittle and serpent starfish, small hermit crabs (but not arrow crabs since they like to eat fish at night), as well as many of the smaller molluscs and bivalves. Invertebrates make for a more successful aquarium. Anemones aid water quality by their filter feeding activities. Hermit crabs and starfish make good bottom cleaners. They eat the food missed by the fish. Molluses such as flame scallops and spiny oysters are also good water filter feeders while small octopus and live olive or margin shells burrow into the media and keep it clean of large debris. All invertebrates add to the basic balance of a saltwater aquarium as well as making a more interesting tank.
Selecting Your Saltwater Fish: A suggested grouping of fish and invertebrates for a 30-gallon marine aquarium:
1 pair banded coral shrimp
1 pair pistol shrimp with spiral anemone
1 small hermit crab
I small starfish or brittle starfish
2 sea anemones
2 flame scallops
I margin shell
Marine algae such as Penicillus species
Halimeda species and Cauleupa species
1 pair neon gobies
2 jawfish or worm gobies
I cardinalfish or
2 Centropyge species of
2 bass lets
Do not add all of these fish and invertebrates all at once. When your system is set up and ready, you can add your algae, pistol shrimp and spiral anemone, and starfish as well as your cardinal fish or hawkfish. Ten days later add your hermit crab, margin shell, and sea anemone and two basslets. Ten to fourteen days later, add the remaining invertebrates, neon gobies, butterflyfish and hogfish. Add the centropyge species two weeks later as they are the most aggressive of this selection. Remember, before any fish is placed in your main aquarium, they should be quarantined in a medicine tank first.
Selecting Your Saltwater Fish.