I'm new on this , got a calibrated tds meter and here we go.
Had some issues with excess of cal, my run off with phed water no food was 1700-2200. Flushed and then half dose nutes without cal-mag, did that 2 times. Ppm dropped to 1100-900
3 days ago I fed my girls, water ppm 1200, runoff 1200...