Hello chopficaro,
There are microorganisms in any
nutrient solution. There are both beneficial, as well as pathogenic microorganisms, the key is balance. Even to much of a good thing can be bad. If they are using molasses as an ingredient, I would say that the amount in their formula takes that into account. But also possibly the growth stage as well. As he mentioned nitrogen is needed more during vegetative growth, not as much during the flowering stage (assuming they are not continuously flowering plants). But if you want a better or more specific answer, I would e-mail them directly. They make them, they should know the reason they use the ingredients in them.