First, by babies got brown tips/spots round the leaf edges, so I read lots of posts and figured 'nute burn'. I stopped the miracle grow treatment and just carried on with clean water to flush out the excess nutes. Now, they have brown spots in the middle of the leaves and are curling down at the ends. I am watering only when the compost is dry. I have no infestation. I have 'em under a 400W MH lamp on 18/6 for veg. Now I wonder if the latest spots are because of mineral deficiencies. How do you tell the difference. I mean, a spot is a spot isn't it? I couldn't get a good photo, so I drew a picture (attached). This is the first crop I've tried for about 10 years. I thought it was all going so well. Please help.