Thanks again Weedhound, pulled my lights up last last night, the plants are looking happier today, the problem hasn't spread to any other leaves and they showing new growth. My temps 72 humidity 52. I do think i had the lights too close, the leaves that it affected are sort of burnt yellow coloured, dry and a bit crispy, as for the soil, it says on the bag no nutrients needed for 30 days, so thats what i'll do. I Didn't realise White Widow were of a delicate nature, hopefully i've not harmed them too much. Fingers crossed!!