New research published in Scientific Reports explores a novel and sustainable protein source for aquaculture feeds by raising black soldier fly larvae (BSFL) on treated poultry wastewater sludge. The study found that the larvae fed on sludge treated via electrocoagulation and flocculation — processes that significantly reduce organic contaminants — achieved 5–8‑fold increases in body weight over 15 days, indicating strong growth performance.
BSFL are already considered a promising alternative to traditional animal‑based proteins such as fishmeal, thanks to their high protein content, fast growth and low production footprint. This research advances the concept by demonstrating that industrial and egg‑processing wastewater sludges could be repurposed as a larval growth medium, effectively valorising waste streams while reducing input costs.
Under optimised conditions, electrocoagulation using aluminium electrodes removed high percentages of chemical oxygen demand (COD), ammonia and phosphates from wastewater, producing a sludge that supported robust larval growth. Larvae raised on treated sludge showed some of the highest weight gains reported in the study, highlighting the potential of this approach to produce BSFL‑based protein ingredients for aquafeeds.
For the aquafeed sector — which is actively seeking sustainable, scalable and circular ingredient solutions — this study points to an innovative intersection of waste treatment and insect protein production that could reduce reliance on traditional fishmeal and pressure on capture fisheries in the future.
