How to choose a good water-soluble fertilizer with large amounts of elements

The first thing to look at product packaging is that formal packaging is strictly restricted by the state, with detailed records of the common name of the product, manufacturer, main ingredient content, implementation standards, and registration documents for crops;
Secondly, based on the product's usage characteristics, it is a legitimate water-soluble fertilizer that is completely soluble without residue. On the one hand, it is well absorbed, and on the other hand, it is also designed for drip irrigation. If there is insoluble residue precipitation, it indicates that there are many impurities and poor quality;
The third factor is the quality of the product, whether the thickness is even or not. Regular fertilizers require a strict mixing process to ensure uniform composition and stable effect.