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Calcimator

Nutrient Solution Calculator

Calculate hydroponic nutrient solution concentrations (N, P, K, Ca, Mg) in ppm from concentrate dosage, solution strength, and reservoir size.

Inputs

mL/gal
%
gal

Results

Nitrogen (N)

125 ppm

Estimated EC

0.55 mS/cm

Phosphorus (P)40 ppm
Potassium (K)100 ppm
Calcium (Ca)90 ppm
Magnesium (Mg)30 ppm
Total Dissolved Solids385 ppm
Total Concentrate Needed100 mL
Total Concentrate (oz)3.4 fl oz
N-P-K Ratio1 : 0.32 : 0.8
Reservoir Liters75.71
How to Use This Calculator
  1. Enter the concentrate dosage (mL/gal) from your nutrient product label and the solution strength percentage for your crop stage.
  2. Enter your reservoir size in gallons to calculate the total volume of concentrate needed.
  3. Review individual nutrient PPM outputs (N, P, K, Ca, Mg) to verify your solution matches your crop's target profile.
  4. Check Total Dissolved Solids (ppm) and Estimated EC (mS/cm) — compare to your target EC and adjust dilution accordingly.
  5. Use Total Concentrate Needed (oz) to know how much of your nutrient product to purchase per reservoir change.

How the result changes with Concentrate Dosage

Concentrate DosageNitrogen (N)Estimated EC
2.4561 ppm0.27 mS/cm
7.32183 ppm0.81 mS/cm
13325 ppm1.43 mS/cm
18450 ppm1.98 mS/cm

What each input means

Concentrate Dosage
Milliliters of liquid nutrient concentrate per gallon of water, as recommended on your nutrient label. Most 3-part systems use 2-8 mL/gal.
Solution Strength
Percentage of full-strength nutrient solution. Seedlings use 25-50%, vegetative growth 75-100%, flowering/fruiting 100-125%.
Reservoir Size
Total reservoir capacity in US gallons. Larger reservoirs provide more stable pH and EC between top-ups.

How this is calculated

Worked example, using the default values

  1. Identify Input Parameters
    Concentrate Dosage = 5, Solution Strength = 100, Reservoir Size = 20 = 3 input(s) provided
  2. Calculate Nitrogen
    Nitrogen
    125 = 125
  3. Calculate Estimated EC
    Estimated EC
    0.55 = 0.55
  4. Calculate Phosphorus
    Phosphorus
    40 = 40
  5. Calculate Potassium
    Potassium
    100 = 100

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