"Manufactured
nutrients are manufactured to be balanced in the first place."
Impossible to rely upon with the varying concentrations of calcium and magnesium present in municipal and city tap water. Also, the numbers on the bottle are a minimum guaranteed analysis. It could be higher than that and they don't have to tell you. I learned this the hard way when a batch of GH had way too much magnesium vs calcium in the micronutrient part of the 3-part flora series.