Nitrogen, phosphorus and potassium are the main nutrients in fish ponds. In the aquaculture process, the nitrogen, phosphorus and potassium in the aquaculture water are mainly supplemented by applying inorganic fertilizer and fermented farmyard manure.
Under normal circumstances, the nitrogen component in fish ponds is not easy to lack from June to September. Because of the high water temperature in summer, fish feed actively, and the amount of food is increased. Excess protein in the feed is converted into nitrogen by the metabolism of the fish, and the feces are discharged into the water body. At this time, the nitrogen in the water is sufficient or even excessive.
Similarly, the content of potassium in fish ponds in summer is not easy to lack. Because many farmers need to reduce the cost of cleaning up, they often do not clear ponds and overly thick silt for many years often cause eutrophication. These nutrient-rich sludges are often stirred up and floated in the water as a result of fish activity or the convection of the water body, so that the potassium will appear sufficient or even surplus.
Phosphorus is easily deficient in June-September. Due to the requirement of weak alkaline water for aquaculture, weak alkaline conditions are usually achieved by splashing lime into the water body. After lime is splashed into the water, the available phosphorus in the water will be combined with the calcium ions in the quick lime to produce a precipitate of calcium phosphate, so that the original phosphorus can not play its due role and lead to phosphorus deficiency. According to relevant data, the available phosphorus concentration per liter of pond water in the summer is often less than 0.01 milligrams. Phosphorus deficiency affects the growth of planktonic algae, limits its photosynthesis, and then affects dissolved oxygen in water. Therefore, phosphorus should be added to the water from June to September.
Knee Warmer is using batteries as power supply, to reduce pains of the knees. It provides stable heat penetrating so as to relax fatigue caused to the knees.
It is always with velcro for fastening better, which also enhance the heat therapy effect, as it touches better to human knees.
Below picture for reference, it can be made in different shapes and designs.
Knee Warmer
Knee Warmers for Arthritis, Specialized Knee Warmers, Electric Knee Warmer, Thermal Knee Warmer
Ningbo JustLive Electrical Appliance Co., Ltd , https://www.makeheat.net