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In culturing mud crabs and shrimp, you must maintain the water quality properly. It is critical for the healthy growth of mud crabs and shrimp. Poor water quality will result in a higher mortality rate. There are several parameters you should keep your eyes for in the system’s water. Dissolved oxygen, pH, ammonia, nitrite, calcium, magnesium and phosphate levels are all included. In this blog post, we are going to share the test kits and equipment needed in your farm for water quality checking.

The following list is not arranged according to its priorities. Number one, you would need a dissolved oxygen test kit. Dissolved oxygen level means the amount of oxygen available in the water. If you fail to give the appropriate oxygen level, the animals will die.

Number two. pH test kit. If your water is too acidic or too alkaline, it can affect the growth of your stock and susceptible to diseases. For shrimp, lower production levels will occur. Water with a low pH level would need to be added with sodium bicarbonate until desired. In the other hand for too high pH, it is not usually a case for indoor farm as high pH is typically caused by high amount of algae in the system.

Number three. Ammonia test kit. In both Recirculating Aquaculture System and Biofloc system, ammonia can be produced from the decomposition of organic matter like uneaten feed or faeces from the animal itself. If you haven't or never checked your ammonia level, make sure to have the ammonia test kit for your animal’s lives.

Number four for monitoring water quality, nitrite test kit. At 2 ppm (mg/l) and above, nitrites are toxic to the animals.

Number five and six, calcium and magnesium test kit. Without an inadequate level of calcium and magnesium, your aquatic animals will face stress, and problems during the molting process. This is because they need both calcium and magnesium to molt. Thus why you need to have these two so you can check the calcium and magnesium levels of your water.

Last but not least, number seven, phosphate test kit. Phosphate is also released in the water from uneaten feed, faeces, and dead bodies of the animals.

That are all the test kits you might want to consider having in your farm. Test kits are not cheap, you will probably not need to measure the water quality everyday. However, that doesn’t mean that you don't need to measure it at all. In farming, we need to balance cost versus risk. Instead of facing the risk of high mortality rate which affects the profit, we invest to test kits for maintaining a good water quality for the animal's life. Plus, most of the test kits can be used until 60 tests. You can follow the water quality SOP that we use in the house through this link. The test kits and equipment list are all listed, together with the table for your water quality checklist.

Next, equipments for water quality checking. Number eight, Imhoff settling cone. In your system, settleable solid or floc can form from uneaten feed, feed fines, faeces, and algae. That’s why you need to measure the floc using this cone. High floc will affect the rise of ammonia level, and vice versa.

High floc will affect the ammonia level

Number nine, refractometer. It is used to measure the salinity of your water, which is important for reproduction and growth. For mud crab, the optimum salinity is 13 to 15 ppt, while for whiteleg shrimp as we have in RAS Aquaculture, the optimum range of salinity is between 10 to 15 ppt.

Putting the water on surface area to check the salinity

Salinity reading inside of the refractometer. In this picture, the salinity is 15 ppt

That’s all for water quality SOP. Do you have most of the test kits or equipments above? Again, it is critical to monitor the ideal water quality for farming as mud crab and shrimp mostly live in the water. Plus, we want to prevent the animals from less production, shrink growth, and even high mortality rate. This would lead to loss of profit, which is not good for the business.

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