Nutrient mix calculator
Enter your reservoir and the feed chart's dose for each part. The calculator gives the millilitres to add, at full strength or less.
Add each part to the water separately and stir between them. Never mix concentrates together: some parts react and precipitate when concentrated. Check pH last.
How it is calculated
Each part's amount is its dose rate times the volume of water, scaled by the strength you choose:
mL to add = dose × volume × strength ÷ 100
A dose given per US gallon is converted with 1 US gallon = 3.785 L. Use the strength setting for a half-strength top-up or a gentle first feed.
Why ppm meters disagree
Meters measure conductivity (EC) and multiply it by a factor to show ppm. The factor depends on which salt the meter assumes: 500 for sodium chloride, 700 for potassium chloride, and 640 on some others. The same water can read 900, 1152 or 1260 ppm. EC is the one number that does not depend on the meter.
Dosing by volume, automatically
GrowRoom's dosing pumps are designed to do this arithmetic's last step for you: each one dispenses a set volume in 0.1 mL steps and counts what it delivered with its encoder, with up to eight nutrient and two pH pumps per controller.
Status: the pump driver answers commands on the bench; no real dose has been run yet, so there is no accuracy figure. The dosing pump