From my Freshwater Aquaculture Book:" Animal dung, green manure, and seed meals are used as nitrogen sources. ....bird manuers tend to be more acidic than others. Some researchers believe that dung promotes the growth of both phyto and zooplankton while green manures are effective only for zooplankton. Zooplankton grows particularly well with seed meals, apparently because it can make direct use of their proteins. Both types of manure are said to be faster acting if properly composted. Certainly compost is less likely to deoxygenate water than raw manure.""
Using organic manure effectively is probably as much art as science, and maybe more art than science. DO crashes are likely when using organics as pond fertilizer. Organic manure grows lots of bacteria.Bacteria uses lots of DO while being a food source for both the planktonic and benthic microanimals. Thus the brown water was probably filled with bacteria observed by CB1?. Bacteria is fed on by many types of zooplankton (protozoans, rotifers, and microcrustaceans) including the ones planktonic and those associated with the decomposing organic materials lying on the bottom. Zooplankton feeds fish. This is probably why manure is more of a direct route than inorganic / synthetic fertilizers which first grows phytoplanton- blooms and green water.
Last edited by Bill Cody; 02/05/12 05:57 PM.
