Nutrient Solution Calculator

Each nutrient's ppm is calculated as that nutrient's base concentration multiplied by your Concentrate Dosage and Solution Strength, so Nitrogen, Phosphorus, Potassium, Calcium, and Magnesium all scale up or down together whenever you change the dosage — none of them can move independently of it in this calculator. A real nutrient line behaves the same way in practice: concentrate mixed at a higher rate delivers proportionally more of every nutrient it contains, not just one.

Solution Strength is a percentage multiplier applied to every nutrient's ppm before they're summed into Total Dissolved Solids, and Estimated EC is derived directly from that total — so a higher strength percentage means more dissolved nutrient salts in the same volume of water, and EC (a measure of how well the solution conducts electricity, which rises with dissolved ion concentration) increases along with it. This mirrors real hydroponic practice: EC readings climb as you feed at a higher percentage of full strength.

No — Reservoir Size only affects how much total concentrate you need to add (Total Concentrate Needed) and the reservoir's volume in liters, not the ppm concentration itself. Concentration depends only on how much concentrate you add per gallon (Concentrate Dosage) and your Solution Strength setting; a 20-gallon and a 200-gallon reservoir mixed at the same mL-per-gallon rate and the same strength percentage will have identical ppm, just very different total volumes of mixed solution.

This calculator's EC figure comes from converting estimated total dissolved ppm using a commonly cited approximate factor, but real EC meters measure conductivity directly and different meters (and different ppm-scale conventions used across the industry) can report meaningfully different numbers for the same physical solution. Treat Estimated EC as a rough planning figure, and always trust a calibrated EC meter reading from your actual mixed reservoir over this calculator's estimate when precision matters.

Solution Strength is meant to mirror the standard hydroponic practice of feeding weaker solutions to young or sensitive plants and stronger solutions to established plants: many growers use roughly 25-50% strength for seedlings and clones, 75-100% for vegetative growth, and up to 100-125% for flowering or fruiting stages, though the right numbers always depend on your specific crop and nutrient line's own feeding chart.