Give Your Pet Fish a Happy Home

October 27, 2014 in Aerowood Animal Hospital

While home fish tanks and aquariums appear to be a serene and relaxing environment, a recent study finds that the pet fish that live in them may feel otherwise. In fact, the study shows that fish are at risk of becoming aggressive when kept in smaller, cramped bowls or tanks compared to living in larger aquariums with more complex habitats.


For the study, author Ronald Oldfield compared the behavior of popular pet fish Midas cichlid in a variety of environments. The fish were observed in their natural habitat in a crater lake in Nicaragua, in a large stream in a zoo, and in different size tanks that are commonly used by pet fish owners. Oldfield used only young fish to remove the possibility of mating being the cause of aggressive behavior. Likewise, the research was conducted in ways so that the fish were not competing for food and shelter. In addition to tank size, the study also looked at the complexity of the environment and the effects of the number of fish within the tank.


The fish placed in the smaller, barren, and crowded tanks were more likely to show aggressive behavior including flaring their fins and chasing, charging, and attacking the other fish. When placed in larger, more complex environments with rocks, plants, and other objects, the aggressive behavior declined.


In summary, larger tanks with interesting features inside make for happier, more naturally behaving fish.


Source: Oldfield R. Aggression and welfare in a common aquarium fish, the Midas cichlid. Journal of Applied Animal Welfare Science, 2011; 14 (4): 340-360.

Fish Happy

Print Friendly