interesting knight...I had no idea I would get such mixed answers from everyone here on the ppm issue.
My ppm is currently at 500 and 4-5 of them are looking really healthy finally with some new growth. 4-5 is not 20 thou....
some plants look overwatered and wilting while others are a 1/4" higher up, dryer and also wilting. The most healthy plants are lower down, getting saturated and taking advantage of the 4 hour dry time.
I am certian that a large part of my problem is my nutrient solution. I have had much easier experiences growing with the organic version of GH nutes floranova etc. I will stick to this in the future unless I have success with this lucas formula that was brought 2 my attention.