just got a bluelab ppm pen and it has 2 settings. (500ppm or 700ppm) Which setting should I be using? Coco based medium. It also has ec but I don't know what the ppm or ec should be.
Preference look up the blue lab chart it has everything blue lab related setting wise. I used the 700 but now with the og of the game dutch pro we are running on ec. Sent from my SM-G925R4 using Grasscity Forum mobile app
Ec is usually more accurate, because that's what is used to calculate ppm. It's just the electrical conductivity of all nutrient salts in the water. Ppm can be calculated a few different ways with the Ec, making it kinda hard to figure it out. But then again, most nute companies list their feedings in ppm. I'm not sure which setting is for ppm is better though Sent from my VS985 4G using Grasscity Forum mobile app