This thesis describes the cost price of microalgae production in aquaculture hatcheries and the effect of cost reduction strategies on the biomass quality. With the developed techno-economic model, the cost price of microalgae production in state of the art aquaculture hatcheries is assessed. Two different reactor systems are compared under conditions using artificial light or only sunlight. Calculations are based on production data of industrial microalgae production facilities in aquaculture hatcheries. Experimental data obtained at laboratory and pilot-scale using Rhodomonas sp. revealed the combined effect of temperature and light conditions on the biomass yield on light and the fatty acid content and composition of the algae. Combing the experimental data and techno-economic model shows the effect of cost reduction strategies, such as changing growth parameters, on the biomass composition and cost price. The outcome of this thesis will help aquaculture industry develop cost efficient microalgae production strategies.