Yeah I have always been plagued with Red Stems since I started growing. In fact I have yet to have a grow (diffrent strains) that don't go purpal.

I get great results ither way. Would I love to toally nail down the problem of course but I don't let it stress me out ither.

I found a Little Folier feed with some Bloom fertz (K) Helps me from getting anymore purpal stems, but in my experience they have never gone from Purpal back to green. However I have noticed the veins of the plant will turn from redish to green again.

kd