Human vitamins are formulated for utilization by the "human" body, not plants.
WHoa! "Hydroponics Forum". I am NOT a water farmer, and am not familiar with hydro chems or ferts. I apologize.
But, I don't believe that I have mis-informed you in any way.
has some pretty good hydro links
Over twenty elements are needed for a plant to grow. Carbon, hydrogen and oxygen are absorbed from the air and water. The rest of the elements, called mineral nutrients, are dissolved in the nutrient solution. The primary or macro- nutrients (nitrogen (N), phosphorus (P) and potassium (K)) are the elements plants use the most. Calcium (Ca) and magnesium (Mg) are secondary nutrients and used in smaller amounts. Iron (Fe), sulfur (S), manganese (Mn), boron (B), molybdenum (Mo), zinc (Zn) and copper (Cu) are micro-nutrients or trace elements. Trace elements are found in most soils. Rockwool (hydroponic) fertilizers must contain these trace elements, as they do not normally exist in sufficient quantities in rockwool or water. Other elements also play a part in plant growth. Aluminum, chlorine, cobalt, iodine, selenium, silicon, sodium and vanadium are not normally included in nutrient mixes. They are required in very minute amounts that are usually present as impurities in the water supply or mixed along with other nutrients.