Preliminary Assessment of Microalgae, <i>Chlorella vulgaris</i> , and Black Soldier Fly, <i>Hermetia illucens</i> Larvae, as a Viable Alternative Feed Combination for Red Hybrid Tilapia, <i>Oreochromis</i> sp. Culture

This study evaluates the potential of microalgae, <i>Chlorella vulgaris</i>, and black soldier fly larvae (BSFL), <i>Hermetia illucens</i>, as an alternative complete diet for red hybrid tilapia, addressing challenges arising from declining fish stocks and unsustainable aquaculture practices reliant on fish meal in commercial pellets. The study involved 270 tilapia separated into three groups: Group 1 received <i>C. vulgaris</i> alone, Group 2 was fed with a combination of BSFL and <i>C. vulgaris</i>, and Group 3 with commercial pellets (control) for 70 days. The results demonstrated that the combination of BSFL and <i>C. vulgaris</i> had a high potential to be an alternative to commercial pellets, with comparable growth performance with the control group. In contrast, fish-fed with <i>C. vulgaris</i> alone exhibited significantly slower growth rates and higher mortality. Economic analysis showed that the BSFL and <i>C. vulgaris</i> combination reduced feed costs by 59.40% and increased the profit index by 144.79% compared to the control group. However, the combination diet did not provide significant protection against streptococcosis compared to commercial pellets. This study highlights the potential of incorporating BSFL and <i>C. vulgaris</i> into tilapia diets to enhance sustainability and economic outcomes for farmers. It also emphasizes the role of alternative feeds in promoting environmentally sustainable aquaculture practices, with the goal of achieving zero-carbon emissions. This study is the earliest report on the direct combination of BSFL and <i>C. vulgaris</i> diet in tilapia, a globally cultivated aquaculture fish species.