I like hydro ph from 5.6 to 6.2 ALWAYS.

what is minus 31 ec and how often do you calibrate your meters?
Weedhound Reviewed by Weedhound on . leaves turning light green to yellow hi all i hope you can help i have 6 plants, since day 1 4 of the plants have a few leaves turning lighter and lighter green with dark green veins some leaves have a burned tip and edge, the leaves are straight except very tips bend down they are 2 weeks into 12/12 E-indoor or outdoor - indoor 5x9x8 sealed, 6in exhaust fan, 2-4in fresh air openings Rating: 5