FertCalc is a very simple calculator written in python for the purpose of calculating fertilizer injector ratios for desired PPM of an element in a output solution.
NPK Nitrogen Phosphorus Potassium EX. 18-6-18
EXAMPLE of what calculator will do for you so you dont needa do maths N=18 18/100 = .18 .18 * lbs (75) = 13.5 13.5 * 453.34 (grams/lbs) = 6123gramsN ((6123gramsN / (gallons of stock water)*liters/gallon(3.79L)) * 10^6)/10^5 = 32,358 ppm N in stock tank 32,358(ppm in stock tank)/desired ppm (ex. 200ppm) = 161.7 injector ratio = 1:162