Aquaponics in urban environments is emerging as an alternative to provide food that meets protein and vegetable needs with low carbon footprint, close to the consumer and at a reasonable cost. The Universidad Pontificia Bolivariana (UPB) in Medellín, Colombia, has built a laboratory as part of the "Technologies in Urban Agriculture" research program. The laboratory is a 160 m2 greenhouse (Fig. 1) located in the middle of the city that houses several projects, with the Urban Aquaponics Laboratory (UAL) occupying the largest space. The purpose of this space is to serve both research and teaching.
UAL is divided into a laboratory for experimenting with new food sources for tilapia and a demonstration aquaponics facility with two tanks of 2000 l each and different hydroponic systems (substrate, NFT and floating rafts). The limited space available has been a challenge that has developed our creativity to make the best use of the space.
Some of the differentiating elements of the UAL are the solar panel system with energy storage for up to 4 hours, which supplies energy to what we call "essential" equipment (pumps and blowers), so that less energy is consumed and there is a backup in case of a power outage. We also developed a facility to test new foods, such as Andean oilseeds and insects, to reduce costs and dependence on imported inputs. Control systems were developed to regulate the temperature of feed tanks and turn other equipment on and off.
We have also made mistakes in design and implementation, but we have learned great lessons from them that we would like to pass on to all those who venture into the development of new projects, whether in research or business. The design and implementation of this space has required the application of knowledge in biology, hydraulics, IoT, electricity, electronics, materials and a lot of common sense. One of the characteristics of the laboratory was the use of easily available or recycled materials, so that the system can be easily replicated by the users of the different trainings that will be carried out. The sum of all this knowledge and experience will serve to support STEM education at different educational levels.
The implementation of these kind of facilities for education and research in urban aquaponics is an opportunity for knowledge of this technology to reach more people and contribute to food sovereignty and security in a more sustainable way.