After changing your pond dirty water, buy 250grams of salt divide into two equal part and pour half portion in 30 litres of water.
You can use 25 litres gallon for the measurements then you add another 5 litre gallon to complete 30 litres. Or you use 50 litres and 10 litres gallon for 60 litre measurement.
You can measure as many 25litre salt water as possible to make sure it cover all the fishes properly.
Mix very well and pour in pond then leave the fish to drink the salt water (salt solution) for 30 minutes. By the 30 minutes time increase your pond water to the Normal level.
You see your catfish always healthy and no death.
TAKE NOTE:
Please if know you will add more than this measurement, don't try this method because over dosage will kill your fishes.
Good day and enjoy your business profits.
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