Why are some nutrients split into an “A” and “B” formulas?

Nutrients are split into two formulations because the phosphorus, calcium and sulfur nutrients need to be separated from each other. If this is not done, then the calcium and phosphorus, as well as the calcium and sulfur, in high concentrations, will react with each other to form calcium phosphate (cement) and calcium sulfate (gypsum). Both calcium phosphate and calcium sulfate precipitate out of solution, forming a white precipitate (which will usually fall to the bottom of the reservoir), and are unavailable to the plants. This will cause phosphorus, calcium and sulfur deficiencies in the plant. Once these nutrients are mixed together in the reservoir they are at lower concentrations and also a pH balanced nutrient mix will prevent the three nutrients from reacting with each other. This is another reason why balancing pH is extremely important. Some nutrients are one part such as FloraNova Grow and Bloom, are extremely thick and need to be shaken well before mixing into the ...