Comparison between cage and pond production of Thai Climbing perch and Tilapia
Water quality parameters
Production of sufficient fish food organisms depends on the water quality parameters. In this experiment,
water temperature ranged from 15.3°C to 28.5°C. Boyd (1982a) reported that the range of water
temperature from 26.06 to 31.97°C is suitable for fishculture. Taking the winter season into account, it
may be considered that the range of water temperature was within the acceptable range of fish culture.
The mean water transparency in Caged Tilapia ponds was lower (25.98cm) which indicated that open
pond Thai Climbing Perch did not effectively consume the natural food organisms developed due to the
nutrients derived from cage wastes. Suitable dissolved oxygen concentrations were found in the ponds,
because of addition of freshly oxygenated water from the deep tube well. According to Swingle (1967) pH
from 6.5 to 9.0 is suitable for pond fish culture and pH more than 9.5 is unsuitable. The measured pH in
the present study in different treatments was slightly alkaline (7.0mg l
-1
to 8.9mg l
-1
) which indicated good
productivity of the pond water.