Aquaponics involves the simultaneous production of plants and fish and it is increasingly being used with a self-consumption purpose. However, there are uncertainties and little information about the economic sustainability of small-scale self-managed aquaponic systems. The objective of this study was to obtain economic information about these systems, including the level of commoditization of food production as a measure of their autonomy. For this purpose, two small-scale aquaponic systems (SAS) based on FAO models were self-constructed using cheap and easy-to-obtain materials and monitored for a year. A total of 62 kg of tilapia and 352 kg of 22 different vegetables and fruits were produced, with an average net agricultural added value of 151.3 €. Results showed positive accounting profit but negative economic profit when labor costs were included. The degree of commoditization was around 44%, which allows a certain autonomy, thanks to the use of family labor force.

Aquaponics is a sustainable food production system combining hydroponics and aquaculture. Although the domestic/small-scale aquaponic production has proliferated worldwide, there is scarce knowledge about how it is performed. The objective of this study was to determine the profile and motivations of aquaponic producers, the characteristics of the facilities and the performance of the production. The average aquaponic producer is a middle-aged man, with a certain level of studies and a moderate household income. The main motivations reported were the production of high-quality, healthy food, the concern for the environment and the autonomy gained. These motivations conditioned the purposes of the aquaponic facilities (mainly education, production of food for self-consumption and as a hobby), which, excepting small sales, did not have an economic motive. Due to their characteristics, aquaponic facilities are particularly adapted for urban agriculture (many of them were located on rooftops) and most of those studied were constructed recently. The nutrient film technique was the most used hydroponic subsystem, followed by media beds, where mostly a polyculture of leaf and fruit vegetables and aromatics are produced. Tilapia was the most common fish species used. In general, there is a lack of proper knowledge and expertise about these complex systems in order to efficiently operate them.

Homestead aquaponic production has been proposed as a reasonable alternative for obtaining food within the framework of the circular economy. However, little is known about the ability of homestead aquaponics to contribute to a healthy diet and the savings it represents on the cost of such diets for inhabitants of economically depressed communities. In the present work, based on a case study, the nutritional contribution of vegetables and fish produced in one year has been calculated, with the goal of determining the contribution of aquaponics to the healthy diet of an adult during this study period. The amount of external food products that should be purchased, the nutritional contribution of the complete diet (comparing it with that of a Mediterranean diet), and its cost have also been determined. The results show that achieving a balanced diet in macronutrients, minerals and essential nutrients with aquaponics is feasible, with a real cost of about 3.07 euros per person per day, amounting to a mean savings of 22% compared to the market price of food. The percentage of nutrient contribution of aquaponic foods exceeds in most cases 20%, being especially high for protein, dietary fiber, some minerals such as potassium, and vitamins.