Water is the main medium for surviving fish. Chemical qualities of water influence the livings of fish and control the production of fish. The chemical qualities of water has a favorable rate. A short description of some chemical qualities of the water of fish cultivated pond are described below.
Oxygen essential for life. The oxygen produced by phytoplankton and aquatic plants through carbon assimilation process, get dissolved with water. Some oxygen also get mixed with water directly from air. Fish, aquatic plants and animal of pond continue breathing with oxygen. No oxygen produce at night due to absence of sunlight. For this reason the amount of oxygen in the water at morning get reduced and in evening increases highly. Oxygen is also used for rotation of basal organic substance of pond. 5-8mg dissolved oxygen available per liter water is very suitable for fast growth of fish.
Causes of Decreasing Oxygen in the Water
Causes of decreasing oxygen in fish cultivated water are listed below.
- Rotation of organic substance.
- Harmful bloom.
- High rate of iron in the water.
- Excessive leaves and branches of trees in the water.
- Excessive use of fresh dung.
- Cloudy weather.
- Muddy water.
Ways of Meet Up Oxygen Lacking
- By making wave in the surface of water.
- By moving hand or bamboo in the water.
- By entrancing new water in the pond.
Dissolved Carbon dioxide
Carbon dioxide is very necessary for producing natural food in water. This gas produce in the water due to excessive organic substance and clay in the basal level of water in high temperature. 1-2mg carbon dioxide is very suitable for better fish production. Excessive carbon dioxide can be reduced by using lime at the rate of 10mg per liter water.
Ph meter is used to measure the alkalinity and acidity of water. If the Ph become less than 7.0 then the water is acidic and if it become more than 7.0 then the water is corrosive. Water with Ph level 7.0 is neutral. Comparatively corrosive water is better for fish farming. But excessive alkalinity may hamper the health of fish. On the other had acidity is also very harmful for fish. The fish feels no appetite and production get reduced in acidic water. Suitable Ph level for successful fish farming is 7.0-8.5.
Total alkalinity of water is measure by calcium, magnesium carbonate or bicarbonate. Productivity of pond is mostly depends on the total alkalinity. Alkalinity rate between 70-200 is perfect for fish farming.
Natural water contains a very low amount of phosphorous. This phosphorous turns to phosphate. Huge amount of phytoplankton grows in the presence of adequate phosphate. Only phosphorous plays a vital role in producing aquatic plants. Abundance of organic substance increases the supply of phosphorous. 0.2mg phosphorous per liter water is necessary.
Nitrogen is the main nutrition ingredients of aquatic plants. Nitrogen has a great role in aquatic production as the element of protein assimilation. Natural nitrogen can’t meet up the demand of nitrogen of any pond or stream. 0.2mg nitrogen per liter is ideal for fish farming.
Potassium is very important for assimilation of phytoplankton. Along with this potassium helps to dissolving the other substances of soil. The water of the pond must have 1 PPM dissolved potassium.