Releasing Aquarium Fish in Malaysian Lakes?

Aquarium fish, Pacu

(photo source: kezj.com)

Most fish hobbyist can easily lose interest when aquarium fish become too big. The fish are no longer cute and become violent. They need more food and a bigger space, a new aquarium. The owner has to spend a lot of money until it is not worth it to keep them anymore. So, the easiest way is by releasing them into a lake with hope that the fish can get plenty of food, enough space, and have a good life in future.    

Yes, they maybe have a good future in the lake, but what effect could the fish have on the lake if they are an alien species (exotic species)? What happen to the original fish that live there?

Some studies report that the effects of releasing fish are competition for food and habitat with the native fishes. Usually the released fish wins because they are larger and stronger. They can easily eat and kill other fish, and even destroy their nest and eggs. The lake will lose many species over a longer period.

In Malaysia, some of the strong and big fish released are dragon fish (arapaima), lake grouper (jaguar cichlid), and pacu. Just imagine this strong and big fish entering a lake, like someone who is violent entering your house and destroys everything. That’s horrible!

Dragon fish (Arapaima gigas)

(photo source: Malaysiakini.com)

So what can we do about it? Some people say we can sell or give them to another hobbyist, or just bring the fish back to the pet shop. In the United States, many people do euthanize, using some kind of chemical to let the fish die humanely. The better solution may be to donate them to the zoo, aquaria center, school, government office, or professional office. Over there, the fish could have a better life and we could save our lakes.