Aquaponics in Malta : integrating African Nile tilapia, African catfish, and crayfish for sustainable food production

Abstract

The report focuses on aquaponics in Malta with a combination of African Nile Tilapia (Oreochromis niloticus), African Catfish (Clarias gariepinus), and Crayfish, providing a closed-loop sustainable aquaponics system. The report aimed to analyse the suitability of each species, design an ideal aquaponics system for the climatic conditions in Malta, and identify plants that are compatible. The methodology involved analysing optimal conditions, components, and how to filter and manage water. Both Tilapia and Catfish grow quickly, and the ammonia-bearing waste produces rich nutrients for leafy greens, herbs, and vegetables, while the Crayfish consume detritus contributed to the sustainability of the entire system. Further, the aquaponics system uses 90% less water than traditional agriculture and is purposefully designed to positively impact the issue of water supply scarcity in Malta. The challenges identified in the project were managing the aggressive behaviour of Tilapia and Catfish, in addition to any risk associated with ammonia-based build-up due to insufficient biofiltration. These challenges can be managed with separation of species and enhanced biofiltration systems. The system proposed to consider a multi-species system with deep water culture and culturing the Crayfish in four media beds which enabled the aquaponics system to remain economically viable while contributing to food security in Malta. Recommendations include vertical aquaponics to improve planting, solar power, and community groups to support sustainable agriculture.