Abstract:
Daphnia magna Straus, 1820, plays a significant role in food supply for fish farming; thus, it
is important to formulate a medium that can increase the D. magna population. This can be
achieved by supplying a direct nutrient for D. magna while supporting the growth of the
phytoplankton and zooplankton population. However, at certain levels, the nutrient source
addition adversely affects the culture medium. This study aims to investigate the effects of
different concentrations of poultry excreta included in a culture medium enriched with
chlorella powder on the biomass production of D. magna. An experiment was conducted by
adding poultry excreta at four concentrations (0, 2, 4, and 6 g·L-1) to the chlorella powder
culture medium. The culture was maintained for 15 days, and samples were collected on
days 0, 5, 10, and 15 to analyze the D. magna population, water pH, and concentrations of
ammonia, nitrate, and dissolved oxygen (DO). Furthermore, a statistical evaluation was
conducted using one-way analysis of variance in a completely randomized research design.
The results showed that an increase in the poultry excreta concentration reduced the water
quality (P < 0.01), as indicated by the water pH and ammonia, nitrate, and DO
concentrations. In addition, a longer duration of the experiment substantially improved the
qualitative parameters evaluated. Similarly, the population of D. magna was significantly
affected (P < 0.01) by both factors. In conclusion, the addition of poultry excreta decreased
the water quality of the chlorella powder medium. The water quality improved on prolonged
days; thus, the highest population of D. magna was achieved on day 15 using 2 g·L-1 of
poultry excreta.
Keywords: Daphnia Magna, Daphnia production, Chlorella powder medium, poultry excreta,water quality.
