Since fish take on the surrounding temperature, they cannot tolerate rapid changes in temperature. This becomes important when stocking and the container water temperature differs from the receiving pond water temperature. The recommended acclimation rate is for every 10 F change in temperature temper fish for 20 minutes. The cooler the water temperature, oxygen is more soluble. That is, there is more oxygen in cool water than in warm water.
Temperature has a major role in pond stratification.
Temperature differences causes density differences. Density differences results in two layers being formed within a pond. Oxygen Dissolved oxygen refers to oxygen gas that is dissolved in water. Fish need oxygen just like land animals do. Fish absorb oxygen directly into their bloodstream using their gills.