pH, EC, and ppm: what the terms mean
Three terms on meters and labels, explained without targets.
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Why these terms come up
Hydroponic growers measure their nutrient solution. Three terms show up on meters and labels: pH, EC, and ppm.
pH
pH is a scale for how acidic or alkaline a liquid is. pH up and pH down are names makers use for products that raise or lower it. Follow their labels.
EC and ppm
EC stands for electrical conductivity, and ppm stands for parts per million. Meters show these readings for a solution, and makers describe them as measures of dissolved nutrients. A TDS meter is a meter makers label for total dissolved solids.
Targets
We do not give pH, EC, or ppm targets. Follow the nutrient label and the maker's instructions.
Handling adjusters
Nutrient products, pH adjusters, and cleaning products are the maker's. Follow the label for mixing, handling, storage, and disposal, and keep them out of reach of children and pets.
This is general information, not legal, electrical, or safety advice.
Sources: CPSC, GFCI Fact Sheet (Pub. 099).
FAQ
General information only. Water and electricity are a dangerous mix: keep plugs, cords, and connections away from water and follow every maker's instructions. CPSC says a GFCI "is designed to protect people from severe or fatal electric shocks" and to test every GFCI "At least once a month." Use a qualified electrician for any wiring. Keep nutrients and other chemicals away from children and pets. In an emergency, call 911.
Next: nutrient solutions
The label sets the mix.
