The purpose of this study was to test polyculture of Nile tilapia and the native Mayan cichlid, as an alternative
production method of tilapia. The experiment had a 2 × 4 factorial design: the first factor was the population
of tilapia (mixed-sex and 95% males) and the second factor was the proportion of Nile tilapia: Mayan cichlid
(3:1, 5:1, 7:1 and 1:0). Proportion of 1:0 was tilapia monoculture. At stocking, tilapias were 11 weeks old and
weighed 24.0 g and Mayan cichlids weighed 5.0 g. Recirculating water systems were used, with 24 fiberglass
tanks 1 m3 with permanent water flow (7 L min−1) and aeration. Each treatment had 3 replicates distributed
randomly, and 24 fishwere introduced in each tank (30 fish m−3). The experiment lasted 21 weeks, until tilapia
reached marketable size.