Lettuce production in aquaponic and biofloc systems with silver catfish Rhamdia quelen

Abstract

Aquaponic and biofloc systems have advantages when compared to conventional food production, but studies that associate both systems are incipient. The aim of this study was to evaluate the development of Lactuca sativa in hydroponic and aquaponic systems (with Rhamdia quelen) with or without bioflocs and using minimal infrastructure. Hydroponic (H-system), aquaponic (Aqua), and aquaponics with bioflocs (Aqua-BF) were evaluated in a randomized design. It did not use a greenhouse, and a single tank to produce vegetables and fish together was used. The stocking density of lettuce was 20 plants m^-2. A total of 168 R. quelen juveniles were used to Aqua and Aqua-BF. Total ammonia, nitrite, and turbidity of the water were higher to Aqua-BF than H-system and Aqua. Lettuces were significantly more productive in Aqua and Aqua-BF than in H-system. There were no differences between Aqua and Aqua-BF for the parameters lettuce production and fish performance. Under the conditions of this study, it was possible to conclude that aquaponics farmers can use silver catfish, and that aquaponic systems with and without bioflocs can improve the lettuce production. The use of bioflocs in the aquaponic system may improve the productivity but needs a better study to optimize and simplify this technology.