Minimum Cations Concentrations in Water Required for Maintanance of Ion Balance between the Amur Sleeper Perccottus glenii (Pisces) and the External Environment

The Amur sleeper Perccottus glenii Dybowski 1877 is widespread in water bodies of Asia and Europe. The species is known to have a harmful effect on aquatic ecosystems, especially by damaging amphibian and fish populations. It was previously shown that based on the determination of the kinetic characteristics, it is possible to reveal the minimum concentrations of sodium, potassium, calcium, and magnesium in fresh water, which are necessary to maintain the ionic balance between the organism of freshwater hydrobiont and the external environment. This study revealed that the minimum concentrations of sodium, potassium, calcium, magnesium in water required to maintain the ion balance between the Amur sleeper organism and the environment are 0.0049–0.0058, 0.0004–0.0005, 0.0004–0.0005, 0.0001–0.0002 mmol/L, respectively. When the concentration of ions in the water is below the limit values, Amur sleeper cannot survive due to the predominance of the loss of ions from the organism. When the concentration of ions in the water is above the limiting values, the flow of ions into the organism is dominated due to the transport from the environment, allowing the accumulation of ions for growth and development.