Bikash C. Mohapatra, Hrushikes
Experiments were conducted in laboratory to observe periphytic growth on four types of plastic sheets, such as polyethylene (PE), polypropylene (PP), fiber reinforced plastic (FRP) and acrylic placed inside the glass aquaria filled with fertilized freshwater for 45 days. Observations were made in every 15th day for growth of periphyton both qualitatively and quantitatively on the plastic sheets, and physico-chemical properties of aquaria water were recorded during periphyton samplings. Significant difference (P<0.05) in periphyton quantity per unit area of the plastic sheets was found among the treatments and the volume from FRP sheet was higher (7.10±0.26 ml/0.1 m2) than the polyethylene (4.43±0.35 ml/0.1 m2), polypropylene (3.35±0.20 ml/0.1 m2) and acrylic sheet (2.32±0.31 ml/0.1 m2). Total 38 periphytic microalgae (Chlorophyceae– 4 types, Cyanophyceae – 11 types, Bacillariophyceae – 15 types and Desmidiaceae – 8 types) were recorded from these sheets. Polyethylene sheet had more types of Cyanophyceae and Bacillariophyceae attached on to it and the acrylic had fewer types. On all sheets Bacillariophyceae (Diatoms) had developed more in numbers and Navicula was the dominant type. FRP sheets can be used as a substrate in aquaculture system for periphytic growth on them, which can be utilized by fishes as natural food.