The Java tilapia, Tilapia, mossambica, is a very efficient pondfish. Total production in ponds stocked with brood fish varied with different rates of feeding from 1,477.1 pounds per acre in 168 days to 4,383.9 pounds per acre in 191 days. Total production varied from 771.1 pounds per acre in 123 days in ponds stocked with 4,000 fingerlings to 2,945.7 pounds per acre in 111 days in those stocked with 20,000 fingerlings. The Nile tilapia, Tilapia nilotica, in limited tests with feeding, yielded a maximum of 4,003.7 pounds per acre in 208 days with adult stocking and 2,380 pounds per acre in 113 days with a stocking of 16,000 fingerlings. Combinations of largemouth bass, Micropterus salmoides, and the Java tilapia produced a higher percentage of harvestable‐sized tilapia (6 inches or more) and a smaller total production than tilapia used alone. Highest production of harvestable fish was obtained by delaying stocking of bass until August, when many tilapias were too large to be eaten. Tilapias spawned when stocked into established bass‐bluegill populations, but very few young survived. Tilapias hatched late in April or early in May reached sizes from 6 to 8 inches within 3 months when adequately fed. The channel catfish, Ictalurus punctatus, the Java tilapia, and the Nile tilapia were almost equally efficient in food conversion and were superior to common carp, Cyprinus carpio, and the speckled bullhead, Ictalurus nebulosus marmoratus. Maximum productions of harvestable fish per acre during one growing season in Alabama were 2,453.1 pounds with the Java tilapia, 2,233.6 pounds for the Nile tilapia, and 2,363 pounds for the channel catfish within 191 days, 113 days, and 252 days, respectively. Increasing rates of stocking of fingerling tilapias decreased rates of reproduction, indicating possible presence of a repressive factor affecting reproduction. The Nile tilapia appeared to be more readily affected and populations of this species contained a higher percentage of harvestable‐sized fish than the Java tilapia. Ponds stocked with brood tilapias April 15 to 20, were opened to fishing the following August. The maximum catch per acre was 593.6 pounds in 1957 and 590.6 pounds in 1958 in ponds stocked with the Java tilapia. The Nile tilapia grew to larger size but were less readily caught by fishermen. The catch of this species was only 128 pounds in a pond containing 1,621 pounds of harvestable tilapia per acre.