Population Dynamics of Daphnia Magna in Artificially, Fertilized Aquarium Ecosystems, and The Implications on Higher Tropic Levels

Unfortunately, the natural or anthropogenic fertilization of ecosystems can have negative impacts on the water quality.  Increased amounts of ohosphorous can lead to water qulaity problems such as eutrophication (algae blooms).  Middleton and Reeder (2003) report that along with fertilization there are several poor water quality conditions that commonly follow including; increased pH, reduced dissolved oxygen, and temperature fluctuations.  Fish productivity responses to changes in these parameters, particularly dissolved oxygen are often negative, reducing total fish productivity (Middleton & Reeder 2003).  Some species of fish are more sensitive to changes in water qulaity, however, temperature is often the most important for all species.  Reducing the negative impacts of increased fertilization on the quality of water the fish are to be reared in is a challenge and one that must be addressed to optimize fish culture productivity (Middleton & Reeder 2003).