Fish/Marine habitats

Marine habitats
Covering approximately 77 percent of the Earth's surface, the saltwater oceans are regarded as a highly stable environment with only minor fluctuations in salinity. The vast ocean waters soon dilute the pollution of fish wastes and decaying organic matter.

Supply of Species
Most marine species available for the marine aquarium come from shallow coastal waters near coral reefs, where fish can be captured easily. Unlike many freshwater fishes, most marine species are still caught from the wild. Despite the attraction and commercial value of their fantastic colors and unusual shapes, marine fishes have proven difficult to breed cost-effectively in captivity, and certainly not in the numbers required for commercial supply.

Specialized feeding
Many marine species eat specific foods, such as sponges, algae, and even the coral itself. Parrotfishes, for example, are beautiful and easy to collect, but they feed only on algae growing on coral rubble. Other fishes with specialized feeding habits, such as the sponge-eating Atlantic angelfishes and the polyp-eating butterflyfishes can adapt to aquarium life if captured very young.

Pools of life
On seashores in all temperate zones, receding tides leave behind tidal pools. These are ecosystems in their own right, containing easily caught schooling fishes, colorful seaweeds and algae, and unusual invertebrates. Although tidal pool dwellers are not as brightly colored as their tropical counterparts, their diverse sheltering and feeding techniques provide a special fascination.