Introduction to the Change Law of pH Value in Breeding
1. Effects of weather changes on the pH value The pH value changes differently in sunny days, cloudy days and rainy days. On sunny days, photosynthesis consumes a large amount of acidic carbon dioxide in the water during the day, and the pH value will rise. On cloudy and rainy days, the situation is just the opposite. Continuous cloudy and rainy days The pH value of the pool water will drop very low and must be adjusted in time.
2. The changing law of pH value in the whole breeding process From the perspective of the whole process of fish and shrimp farming, the pH value of the fertilization and water stage before the seedlings is the highest, sometimes exceeding 9.6, and then it will continue to decline, and even drop below 7.0 in the middle and late stages. Adjustment, the pH value will continue to change.
3. Changes of pH value in a day The photosynthesis, respiration and various chemical changes of aquatic organisms can cause changes in pH value. Therefore, the stronger the photosynthesis during the day, the longer the light time will be, and the higher the pH value will be; at night, when photosynthesis stops, more and more acidic carbon dioxide will be produced by the respiration of fish, shrimp and various organisms (mainly microorganisms), the pH value will be lower. It will gradually decline and reach the lowest level before dawn. If it is a rainy day, the pH changes minimally throughout the day.
Since the toxicity of NH3 and H2S is closely related to the level of pH value, the adjustment of pH value in the middle and later stages must be considered comprehensively. If the concentration of NH3 is high and the concentration of H2S is very low, the pH value can be adjusted to a normal low level at this time. This can reduce the toxicity of NH3 and ensure that it will not cause physiological hypoxia to fish and shrimp; if the situation is just the opposite, the pH value can be adjusted to a normal high level. The general principle is: not only to ensure the normal pH value, but also to reduce the toxicity of NH3 and H2S in the water as much as possible, so as to increase the production of aquaculture.
