I've never used HPS lights but I'm guessing that it's the light that's harming the plant, try some CFLs or make sure the light isn't too close.
phytokind Reviewed by phytokind on . Day 10 from seed/ Here's 2 pics of my plants, there's substantial yellowing on some of the leaves. They are growing in compost designed for tomatos. They are off a 400w HPS lamp, watered every 2/3 days depending on how dry the soil is, no nutes are being added to the water, they are on 18/6. I don't really want to flush the plants but if thats the best course of action I will do. Any ideas guys? Heres some images of the two worst affected plants so far. Cheers guys:thumbsup: Rating: 5