An investigation of a fertilizer-tap water medium for mass algal production in outdoor plastic-enclosed systems

The feasibility of using two fertilizers (urea plus superphosphate) in tap water as a medium for the mass culture of green algae (Scenedesmus and Ankistrodesmus) in outdoor plastic‐enclosed minipond systems was investigated. Experiments in which the basic fertilizer‐tap water medium was enriched with micro‐ and/or macronutrients revealed no nutrient deficiency symptoms in the algal biomass produced. Biomass production was found to be quantitatively related to the concentration of fertilizer added and maximal production (> 15 g/m2 day) was achieved following the addition of 30 mg N/L (1.89 g N/m2 day) and 4.5 mg P/L (0.28 g P/m2/day).