CRESCIMENTO DE ALFACE EM SISTEMA AQUAPONICO SOB DIFERENTES DENSIDADES DE PEIXE E VOLUME DE BIOFILTRO

Abstract

Aquaponics is a real alternative for sustainable food production, enabling an economically viable production of fish and vegetables with the maximum use of water and nutrients. However, information about this technique is scarce in the central west region of Brazil. Thus, this project aimed to evaluate the vegetative development and lettuce yield in an aquaponic system under different tilapia stocking densities and filter volume. The experiment was carried out at Instituto Federal Goiano - Campus Rio Verde, in southwest Goiás. The experiment was carried out in completely randomized blocks, in a 3x2 factorial arrangement, with three replications, the factors being: stocking density (D1= 30; D2= 60; D3= 90 fish per cubic meter); filter volume in relation to the tank (V1=25; V2=35% of the tank volume), totaling 6 experimental plots. Each plot consisted of 1 circular fish tank with a volume of 1 m³, a settling tank and 1 biological filter (both 200 liters) and 1 pump with a flow of 2000 L/h. Lettuce seedlings were formed in phenolic foam. At the end of the cycle, height, number of leaves per plant, plant diameter ("head"), fresh mass of aerial part (leaves), leaves and roots were evaluated. It was concluded that there was an interaction between fish density and biofilter volume for leaf dry mass.