How can you tell if a fish is sick?

Answer by  withluck (1745)

Different sicknesses have different symptoms. A sick fish will sometimes act listless, staying at the bottom of the tank or they may have trouble swimming. They can also show signs of being sick in their appearance. They may be dull or off in color, or have sores or whiteness. Any variation in what is normal for them could indicate sickness.

Answer by  BrendaG (6111)

Check your fish for missing scales and such; if the fish was fighting there may be wounds. Watch your fish's breathing. Watch the fish as it swims for signs of sluggishness. Your fish should have clear eyes with no cloudy effects.

Answer by  Mary15 (347)

If you fish are not acting normal that may actually be a sign. Another sign is if one of the fish actually dies and in the process others do too.