A new and simple medium for phytoplankton culture

Results of the study using a simple medium with a higher concentration of phosphate, developed for isolating unicellular algae from Calicut region are presented in this paper. The new medium is found to be very simple for large scale culture of phytoplankton to develop larval feed in hatcheries. The medium is prepared by dissolving 350 mg of potassium di hydrogen phosphate and 900 mg of p'otassium nitrate in 125 ml di stilled water. One ml of this solution is added to a litre of boiled and filtered sea water. A stock solution of vitamin is made by dissolving 5 mg of B" and 95 mg of B, in 100 ml of distilled water and one ml of this solution is added to each litre of the nutrient mixed sea water. Chromulina sp. Pavlova sp. and Chlorella sp. are inoculated in 250 ml flasks containing the new medium and is simultaneously compared with another set of flasks containing Walne's medium under controlled conditions of light and at a temperature rangong from 28 to 30· C. After every twenty four hours, cell counts are made and it is observed that rapid multipli.:ation of cells occurs during the initial period itself and the exponential phase is continued from the sixth day upto 12th day with similar results in both the media. The results with dirt·erent concentrations of the nutrients in the new medium are also presented in the paper