The fish originally entered Malaysia from Brazil, possibly via Taiwan. The genetic composition of the stock is dubious and is possibly already subject to in-breeding. A total of 14,511 individuals were released in 9 locations (remote lakes in the lower and middle Sepik, Bunapas, in the lower and middle Ramu and Brahman area (Ref. 37808). Started attacking other fishes in the Sepik and Ramu rivers in 1999 when their main food, insects became scarce. There are also reports on human attacks. Causes ecological imbalance by killing local fish and wiping out eggs and fry (Ref. 39336).