On the aquaponic system at the Faculty of Biotechnology in Ljubljana, which includes a 16.5 m² area for lettuce cultivation in the hydroponic part of the system, intensive activities have been ongoing since the start of the project. During the winter months, we cultivated lamb's lettuce on this system, and from March onwards, lettuce. The nutrient source for the growth of the lettuce is the waste produced by rainbow trout (Oncorhynchus mykiss), which is crucial for the functioning of the aquaponic system.
We planted the lettuce on March 15th, April 18th, and May 29th, and with each new planting, we also harvested the previous crop. In total, we produced 523 lettuce rosettes, representing a marketable mass of 70.7 kg. Additionally, we obtained 39.5 kg of waste, consisting of the removed root system and the lower leaves of the rosettes, which were not suitable for marketing. The average mass of one lettuce rosette was 135.3 g. Among all the hydroponic systems tested, the NFT system (Nutrient Film Technique) proved to be the most suitable for lettuce cultivation, followed by the floating hydroponic system (DWC) and the IBC floating system.
This table clearly shows the success of the individual hydroponic systems in different planting periods. The NFT system proved to be the most successful in all terms, confirming its suitability for efficient lettuce production in this aquaponic system.
