The Bacillariophyta Amphora coffeaeformis C.Agardh) Kutzing was grown under indoor laboratory conditions using different nitrogen sources including magnesium nitrate ,nitric acid and urea to evaluate whether the addition of magnesium ions affect the biomass accumulation of the grown alga under this study. Concerning the effect of different nitrogen sources on Amphora growth, data revealed that 59.98 mg.L-1 of Mg(NO3)2 gave the best growth by estimating the biomass productivity of the dry weight of the alga, and the best concentration in increasing the growth rate(0.079)followed by urea then nitric acid concentrations. Different concentrations of magnesium nitrate were studied. The results showed that 50% of magnesium nitrate markedly increases the dry weight accumulation of the examined alga and surpasses control and all other treatments. On the other hand, 2 and 3 folds of magnesium concentrations (100 and 150%) resulted in the maximum productivity in which recorded 0.108 and 0.105 of growth rate, respectively. The excess of magnesium nitrate till 2 fold enhanced dry weight accumulation and 1.5 fold of magnesium nitrate resulted in the maximum (1.38g.l-1)..Scaling up was established to obtain the Amphora biomass based on the laboratory obtained data using 15x14 L photobioreactor with a final capacity of 210 L. The harvested biomass was analyzed for biochemical constituents. Daily growth parameters as dry weight (g.l-1), doubling time (g) and percentage increase (Y) were performed. Biochemical analysis of Amphora coffeaeformis biomass (%)was composed of 31.02 crude protein, 28.37 of total carbohydrates, 13.2 of oils and 12.91 of moisture under ideal laboratory conditions.