An experiment was carried out at the Central Laboratory for Aquaculture Research at Abbassa, Sharkia governorate, Egypt during one growing season for100 days in earthen ponds. The objective of the study was to identify the prevailing water quality parameters and plankton communities in the fish–duck and buffalo manured ponds. The different treatments tested in the present study were buffalo manure (BM), buffalo manure with artificial feed (BM+F), duck manure (DM) and duck manure with artificial feed (DM+F). Each treatment was performed in triplicate. Three species, Nile tilapia Oreochromis niloticus, blue tilapia O. aureus and common carp Cyrinus carpio were used in this study. Results obtained can be summarized as follows:
- Water temperature in treatment ponds receiving artificial feeds was found to be higher than treatments without artificial feeds.
- Pond received artificial feeds showed decreases in pH and alkalinity values in water compared to the other ponds.
- The total phytoplankton counts for treatments BM; BM+F; DM+F and DM were found to be 3570; 5850; 7500 and 10010 organism/L, respectively on the average and Chlorophyta dominated to the other species.
- The total zooplankton counts for treatments DM+F; BM+F; BM and DM were found to be 1906.7; 950; 903.3 and 738.3 organism/ L, respectively on the average and Rotifera dominated to the other species. Other results are discussed in the study. Based on the results obtained it could be recommended the use of duck manure in extensive fish production, thus it increased the phytoplankton counts in the water. In semi intensive production applying the artificial feeds beside duck manure caused a pronounced increase in the zooplankton counts
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