An assessment of algal growth in net cages in Laguna Lake

Abstract

Quantitative determination of the algal population, in terms of cells/ml and biomass/ml, was conducted during the first month of growing P. monodon postlarvae in Laguna Lake. Algae were sampled from each side of net cages at depths of 15, 30 and 45 cm below the water surface. Accumulation of algae appeared to be influenced by the direction of water flow. Moreover, growth of algal species was inversely proportional to depth of water. After two weeks, algal biomass was estimated to reach 4.5 kg per cage (1 x 1 x 1 m).

Diatoms (Chrysophyta) predominated throughout the experimental period followed by members of Cyanophyta and Chlorophyta.