Algae flooding is the death of a large amount or all of the algae in the water body, causing the water color to suddenly become clear, turbid, or even red and black.
One: the reason
1. Caused by high water temperature: The suitable water temperature for diatoms is 23~30°C, and for green algae 25~33°C. When the water temperature exceeds the tolerance level, it will cause algae collapse.
2. The sudden change in the pond water environment caused by the sudden change of weather, resulting in biological imbalance or improper management (including poor timing of fertilization and fertilization; excessive fertilizer and water during high temperature; wrong time and quantity of water and water changes; failure to replenish fertilizer in time after water changes and water additions) ; improper amount and time of use of disinfectant, etc.).
3. The ecological balance of algae is unbalanced, and harmful algae such as cyanobacteria and Gymnodinium are dominant, and the phenomenon of inverted algae and water is caused when the temperature changes suddenly.
4. Excessive use of disinfectants, algaecides and herbicides, insecticides, heavy metal salts, etc. will cause the phenomenon of algae turning into water.
Two: the danger
After the algae is poured, it is easy to deteriorate the water quality due to hypoxia and algal toxin poisoning, resulting in stress reduction of fish, shrimp and crabs, anorexia, decreased immunity, easy infection of diseases, and increased morbidity. Changes in water body (physical and chemical factors) during algae pouring:
1. Dissolved oxygen will decrease and carbon dioxide will increase: This is caused by the lack of algae for photosynthesis in the water. The decomposition of a large number of dead algae will also consume a lot of oxygen. In addition, the increase in carbon dioxide will cause the pH value to drop rapidly.
2. The increase of ammonia nitrogen and nitrite: especially in cloudy and rainy days, the increase is more obvious. The decomposition of dead algae by microorganisms will produce ammonia nitrogen and nitrite. The algae themselves can absorb ammonia nitrogen in the ammonia nitrogen cycle. Now the dead algae cannot absorb it.
3. Water turbidity: The original organisms in the water feed on algae, and the algae will be reduced by the proliferation of the original organisms; if the algae is insufficient, the suspended solids in the water (fine dust, organic debris, feces, dead algae, saprophytic proteins, etc.) cannot be settled, so the water will become turbid.
