I am making a synthetic solution to imitate a real life situation. I am adding calcium nitrate to the solution to meet a target calcium level of 334 ppm. However, using excel calculations the amount of calcium nitrate that is needed imparts a total of 522 ppm calcium. I am also adding 100 ppm calcium carbonate which will increase the levels of calcium. My supervisor said I need to add nitric acid to lower the calcium imparted by the calcium nitrate. How and why does that work? and what calculation do I need to do to figure out how much nitric acid I need to add? I have attached the excel spreadsheet I am working with.