Due to the high cost of potassium persulfate raw materials, fisheries and formulation factories generally choose low content products when debugging and processing. The product specifications only indicate the composition of potassium bisulfate, but its content is unclear, in order to deceive people and sell it at a high price. 

At present, there are a large number of potassium bisulfate products produced by fisheries and formulation factories in the market. However, according to information from several large potassium bisulfate raw material suppliers, the procurement volume of fisheries formulation factories is quite small. This shows that there are a large number of counterfeit products, which is also the reason why some users in the market have lost confidence in the products. In fact, what they sell to farmers is not potassium persulfate, so it will not have a good effect. 

There are several types of counterfeit and inferior products in the market, mainly in the following forms:

1. Use "sodium persulfate+bromochlorohydantoin+dispersant" to compress the tablets. 

2. Granulation or compression using "a small amount of potassium hydrogen persulfate double salt+chlorine gas preparation+dispersant"; 

3. Sodium chlorite+solid acid+surfactant "isobaric tablets; 

4. Use potassium ferrate and other inexpensive oxidants to compress tablets. 

The common feature of these products is that chlorine containing preparations have a pungent odor and can harden the bottom of the pool after use, making them quite affordable.

Methods for distinguishing quality:

1. Is the specific content indicated on the packaging; Whether the packaging is corroded, whether there is color peeling, and whether the cardboard box is damaged. If so, it means that the product is not genuine or the formula is incorrect. The oxidation of the product is not only expressed, but also quite strong. This situation can be used as an important observation standard. 

2. Put the product in a clean mineral water bottle. Gently stir the air at the bottle mouth with your hand and smell the pungent chlorine smell, then it is fake (with a lot of chlorine preparation added). Excellent potassium persulfate products have no odor.