Tropical marine fishes
Marine fishes are the most beautiful candidates for the aquarium, but they are also the most intolerant of changes in water quality. Keeping them is a specialization that should be approached gradually and informatively. Beginning with the more hardy species is less expensive, and is educational.
Tropical marine fishes generally come from coral reefs and coastal areas throughout the tropical oceans of the world. The choice of shapes, sizes, and colors is extensive, and the question of compatibility must be considered during selection. Many marine fishes are territorial, and the may be intolerant of other members of the same species. Hiding places should always be provided. Some species form natural relationships with other fishes or invertebrates, and these may be kept together: anemone-fishes, for example, appreciate the addition of sea anemones.
The breeding of these fishes is often restricted to anemonefishes and gobies.