Choosing A Healthy Fish

Swimming Ability -- A healthy fish will swim without undue effort, and with its fins held erect. A fish that swims with its fins held against its body may be showing signs of illness. A fish that sinks or bobs to the surface when it swims probably has a swim bladder disorder.

Body Shape: A healthy fish will have body contours that are well defined and filled out. Avoid fish that have bumps, boils, pimples, spots, split fins and lumps. Also stay away from a bloated fish with protruding scales, since it may have dropsy. A humped back in a fish is a sign of age.

Coloration -- A healthy fish should have vivid colors. If the fish has patterns, there should be no blurring where the colors meet.