Tilapia serve as a natural, biological control for most aquatic plant problems. Tilapia consume floating aquatic plants, such as duckweed watermeal, most “undesirable” submerged plants, and most forms of algae. In the United States and countries such as Thailand, they are becoming the plant control method of choice, reducing or eliminating the use of toxic chemicals and heavy metal-based algaecides.
Tilapia rarely compete with other “pond” fish for food. Instead, because they consume plants and nutrients unused by other fish species and substantially reduce oxygen-depleting detritus, adding tilapia often increases the population, size and health of other fish.
Arizona stocks tilapia in the canals that serve as the drinking water sources for the cities of Phoenix, Mesa and others. The fish help purify the water by consuming vegetation and detritus, greatly reducing purification costs.
Arkansas stocks many public ponds and lakes to help with vegetation control, favoring tilapia as a robust forage species and for anglers.
In Kenya, tilapia help control mosquitoes which carry malaria parasites. They consume mosquito larvae, which reduces the numbers of adult females, the disease’s vector.
Tilapia also provide an abundant food source for aquatic predators.
In aquaria
Larger tilapia species are generally viewed as poor community aquarium fish because they eat plants, dig up the bottom, and fight with other fish. However, they are often raised in aquariums as a food source due to their rapid growth and tolerance for high stocking densities and poor water quality. The smaller West African species and those species from the crater lakes of Cameroon, are more popular. In specialized cichlid aquaria, tilapia can be mixed successfully with nonterritorial cichlids, armored catfish, tinfoil barbs, garpike and other robust and dangerous fish.