Abstract
Testacealobosia, Arcella vulgaris is well known as the typical protozoa found in the activated sludge and biofilm when nitrification is in progress. The effects of good source, water temperature, pH and phosphate buffer concentration on specific growth rate of A. vulgaris isolated from activated sludge were examined. A. vulgaris was successfully cultured when Chlorella powder suspension media and sludge bacteria were used as food sources. The growth parameters wwere determined using Chlorella powder suspension media. The specific maximum growth rate and half-saturation constant were 1.05d-1 and 1.4TOCmg·l-1, respectively. The growth of A. vulgaris was observed from 10°C to 36°C with optimal growth at 32°C. A. vulgaris was able to grow when the concentration of phosphate buffer was higher than 2/75M and pH value ranged from 4.2 to 9.0. The results show that food concentration and water temperature are the important parameters for the growth of A. vulgaris.
