Ec meter

What EC is

Electrical conductivity: how much electricity the water conducts. Pure water barely conducts; dissolved salts do (and nutrients are salts). So, by measuring EC you know how much fertilizer is in the water or the soil. It is measured in MS/CM.

Reference values

Seedlings: 0,4 to 0,8.

Vegetative: 0,8 to 1,5.

Flowering: 1,2 to 2,0.

Each strain tolerates differently: what matters is how the plant responds.

How to use

You measure the watering water with the fertilizer already in it, to avoid overdoing it. And the draining water: if it comes out with an EC much higher than what went in, salts are building up in the soil and it is best to flush it. Some meters show PPM instead of EC: it is the same thing, on a different scale.