So I have about 12 seedlings, all currently growing under four 100W CFL's and have a small fan running through them to help with temperature and air circulation. The biggest of my seedlings has started to develop small, brown dots or patches on the outside edges of its leaves. They are growing in Miracle Grow Seed Starting Mix potting soil and have been watered once a day (usually when the soil has dried out) since planting. Is this a product of heat burn, nutrient burn, or something else? The brown is like a light brown, the color of clay I suppose. The Miracle Grow Soil seems to only contain soluble nitrate, phosphate, and potash I will be posting pictures later today, but since I dont have access to a camera right now, if you are interested in helping check back in a few hours, should have an Edit with pics.