Scientists from the Agrarian Faculty at the Thracian University in Stara Zagora registered a model of an installation that can raise fish and vegetables in a closed cycle. The patent holders are Prof. Yordan Staykov and associate Professor Ivailo Sirakov.
The installation is designed for the selection of fish, crustaceans, molluscs, and algae. It is integrated for growing low-stem plants such as flowers, herbs, vegetables, etc. There is also an option to include solar panels.
There are two versions of the model - one for start-ups and the other for advanced and financially stable companies. The annual output that can be achieved with this modular type installation is about 10 tons of fish. Interesting here is that the processed organic food residues, which are given to fish, are the liquid fertilizer of cultivated plant species. From each kilogram of fish feed used, nutrients are released and can be a food base for growing 8-10 kilograms of lettuce or 5-6 kilograms of cherry tomatoes.
However, according to euscoop.com, start-ups are expected to reach about BGN 26,000 (€13,000) per year in net operating income. The initial investment is about BGN 30,000 (€15,300) for the production and the installation of the system.