On the mass culture of algae. III. Light diffusers; high vs low temperature Chlorellas

Abstract
Yields (mg/day) of 2 strains of Chlorella were studied in steady-state cultures under a continuous visible irradiance equivalent to full sunlight. For Chlorella ellipsoidea at 25[degree]C the maximum production rate was increased about twofold by use of plastic or glass diffusing cones designed to supply the incident energy over a greater surface at reduced.irradiance. The diffusing cone principle appears to be a practicable means of cir-cumventing the limitations of light-saturation under sunlight illumina-tion. In cultures without the cones Chlorella Tx71105 at 35[degree]C showed a maximum production rate only about 15% higher than that obtained with Chlorella ellipsoidea at 25[degree]C. The bases for earlier expectation of much higher production rates obtainable with high-temperature strains of algae have been re-examined.