STARTUP STAGES OF A LOW-TECH AQUAPONIC SYSTEM

The goal of the project was to establish a low-tech cheap sustainable food production system that combines traditional fish farming with hydroponics (cultivating plants using mineral nutrient solutions, in water, without soil), in a symbiotic environment. We used local fish and plants species only. The project was conducted in two different stages: "construction" stage and "fish" stage. The goal of the start-up stage was to build the grow bed for the plants, to establish the water circuit, to set the lights and to prepare the fish tank for the fishes. For the "fish" stage we used local fish species (carp and caras). The goal of the stage was to build the nitrogen-fixing bacteria colonies in order to provide a constant NO3 í rich water (around 50 mg/l), with as low as possible traces of NH3 / NH4 + and NO2 í (below 0,5 mg/l). This was established by testing the NH3 / NH4 + , NO2 í and NO3 í values under several environmental changes (pH, temperature, lighting, quantity of fish in the tank etc.) in order to identify the best combinations to achieve the goal. Upon completion of the second stage we'll test different local species of plants with the already established system. The goal of the project is to find the best combinations of fish, plants and environmental conditions in order to have a cheap, sustainable symbiotic food production system, easy to be replicated by anyone.