Aquaponics is positioned as a food production system that approaches sustainability. However, there are still some challenges to overcome, these derived from the complexity of integrating its biological components; which still limits crop productivity. Likewise, studies of aquaponic systems have focused on establishing the relationships between fish and plants that allow the highest growth rates; however, the option of linking more than one aquatic and plant species in each production cycle has not been explored. Therefore, the objective of this work is to determine the feasibility of implementing an aquaponic polyculture with tilapia-catfish and lettuce-chard.
The feasibility of implementing a coupled aquaponic polyculture was determined; evaluating the growth of specimens of tilapia, catfish, lettuce and chard. The polyculture worked for 60 days with three treatments: T1 (system with 40 tilapia, 20 lettuce and 20 chard), T2 (system with 40 catfish, 20 lettuce and 20 chard) and T3 (system with 20 tilapia, 20 catfish, 20 lettuce and 20 chard).
The water was monitored in the variables of temperature, dissolved oxygen; as well as the concentrations of phosphate, nitrates, nitrites and non-ionized ammonia. Likewise, biometric data monitoring of fish and plants was carried out. During the 60 days of experimentation, the variables monitored in the water were within the ranges required for tilapia and catfish farming (Table 1). Discarding the influence of water quality as a limiting factor in fish growth. However, the differences between treatments place T3 with the highest concentration of nitrates; which is related to the greater growth of the plants in said treatment.
The fish with the highest growth and survival rate were those present in T1 (Table 2); however, this is not related to the growth of the plants, which in this treatment ended with low growth rates. On the contrary, T3 with a fish growth rate lower than T1 presents the highest growth rates for lettuce (Table 3) and Swiss chard (Table 4).
The study provides information that allows considering the implementation of aquaponic systems coupled with polyculture modality; this with the objective not only of generating food but also diversifying its production.