EVALUATION OF WATER QUALITY IN A SMALL-SCALE AQUAPONIC SYSTEM WITH STRAWBERRY (FRAGARIA × ANANASSA ‘MONTEREY’) AND RAINBOW TROUT (ONCORHYNCHUS MYKISS)

Introduction: Aquaculture is one of the fastest-growing food production sectors, with global output reaching 114.5 million metric tons in 2018, representing a 20.5% increase since 2001.Aquaponics, the integration of aquaculture and hydroponics, offers a sustainable alternative by recirculating water and recycling fish waste as plant nutrients.Aim: This study evaluate nutrient dynamics in a vertical NFT (Nutrient Film Technique) aquaponic system integrating rainbow trout (Oncorhynchus mykiss) and strawberry (Fragaria ananassa).Methods: A 1,800 L vertical NFT aquaponic system was established, containing 100 rainbow trout and 15 strawberry plants.Water quality parameters-including pH, total ammonia nitrogen (TAN), nitrite (NO), nitrate (NO), ferrous iron (Fe), phosphate (PO), and calcium (Ca)-were monitored weekly over a six-month period, with adjustments performed as required to maintain optimal ranges for both fish and plants.Results: The system maintained stable conditions with mean values of pH: 6.52 1.75, TAN: 0.54 0.25 mg/L, NO: 0.03 0.017 mg/L, NO: 96.82 34.83 mg/L, Fe: 0.30 0.18 mg/L, PO: 13.54 6.04 mg/L, and Ca: 62.65 39.47 mg/L.Under these conditions, rainbow trout achieved a mean final weight of 127.86 23.69 g, while strawberry plants produced 15 to 36 reproductive structures (buds, flowers, and fruits) per plant.Conclusions: The findings demonstrate that fish waste especially nitrogen and phosphorus was efficiently converted into nutrients for plant growth, maintaining water quality within acceptable limits and reducing nutrient discharge to the environment.Also the vertical NFT aquaponics is an effective and environmentally friendly alternative for integrated food production.