My plants have got red stems and yellowing leaves i was told two weeks ago I was feeding them too much and the veins was from the build up of nutrients in the plant so I cut the feeddown to under half but now they have got worse with the stems goin completley red and the once lovely green leaves starting to turn yellow and the odd one has got brown spots on them. Are they lacking something? They are 5 weeks in veg and I want to turn them but im not while they are like this. They are in canna coco medium and have only been feeding on canna A and B nutrients. The water has been ph 6.0. I will try and get some pics on later gaving trouble with my fone. Please help thanks.