Abstract:
The purpose of this study was aimed at determining the effects of light intensity, pH values and culture period on growth of Spirulina platensis and Chlorella vulgaris. The light internsities were selected at five levels : 3,000, 3,500, 4,000, 4,500 and 5,000 lux respectively. The pH values used were also selected at five different values, 8.0, 8.5, 9.0, 9.5 and 10.0 and the culture period extended over ten days.The results showed that Spirulina platensis grew best at a light intensity level of 3,500 and 4,000 lux and it produced the best result at pH values of 9.0 and 8.5, respectively. The growth rate demonstrated the highest value on the 10 day among the time intervals used. The Chlorella vulgaris grew best at a light intensity level of 3,000 and 3,500 lux respectively, and at pH values of 8.0 and 8.5. The growth rate demonstrated the highest value on the 9 day among the time intervals used.