"Eco-Friendly Fish Farming: The Impact of Large-Scale Microalgae Cultivation on Fish Meal Substitution and RAS Integration"

he global aquaculture industry is facing mounting challenges due to environmental pressures, including the adverse effects of climate change. Rising ocean temperatures, ocean acidification, and increasing CO2 levels are disrupting marine ecosystems, which has profound implications for the availability of fish stocks that are vital for fish feed. One of the most significant consequences is the depletion of forage fish populations, which serve as a primary source of fishmeal for farmed fish. Overfishing and climate change further exacerbate this problem, causing declines in fishmeal availability and driving up its cost. This situation presents a critical challenge for sustainable aquaculture, a sector that relies heavily on fishmeal to support the growth and health of farmed fish (Islam et al., 2020; Jin et al., 2020).

To ensure the future sustainability of aquaculture and reduce its dependency on marine resources, it is essential to explore alternative feed ingredients. A promising solution lies in the use of microalgae as a substitute for traditional fishmeal. Microalgae, which are rich in proteins, lipids, essential fatty acids, and various bioactive compounds, offer a viable and sustainable alternative for fish feed. Microalgae-based feed not only supports fish growth and immunity but also reduces the ecological pressure on marine ecosystems. Among the most promising microalgae for this purpose are species from the genera Nannochloropsis and Dunaliella, which are known for their high nutritional content and their potential to replace fishmeal in aquaculture feeds.