Identification

Discus fish have round, flat bodies with curved fins. The three original color variants for discus fish were blue, brown and green, but breeders have created discus in almost every color imaginable, and they often feature stripes, dots or other unique markings.

Behavior

While usually peaceful with other fish, discus can become aggressive when around other discus. The behavior is strange in that discus are social fish by nature, and do best when in schools.

Causes

Most aggression in discus fish happens during breeding. Male discus fish attempt to assert their dominance in order to protect their breeding partner. Scarcity of food may also spark aggression.

Prevention/Solution

Keeping a ratio of three female discus fish for every one male is a good way to limit aggression. Regular scheduled feedings throughout the day will also keep squabbles over food to a minimum. Another good idea is to only have discus fish of similar size, so one large fish won't attempt to dominate the others.

Facts

A member of the Cichlidae family, discus fish originated in the Amazon River basin. They get their name from their physical resemblance to a track and field discus.

Source

Aqua-Fish.net

DiscusFishInfo.com

Fish Aquariums Online