What is the difference between humic acid,Potassium humate and potassium fulvate?

The humic acid we usually refer to is also called humic acid powder.
It is essentially the leonardite after sieving and impurity-removing.
The essence of leonardite is organic matter.
The essence of organic matter is humus. And the essence of humus is humic acid, but it is raw material.
By itself, humic acid is insoluble in water, which made it difficult to be applied in agriculture since it is hard to dissolve in water and slow in its effect.
Considering that humic acid powder dissolves in alkaline solution.
we use caustic soda (sodium hydroxide), potassium (potassium hydroxide) or ammonia to activate humic acid and obtain humate such as sodium humate, potassium humate and ammonium humate.
Such activated humic acid products are characterized by high water solubility, high activity and high chelation.
They are mainly used for flushing, drip irrigation and even sprinkler irrigation.