it sounds like you have a damping off problem.this is normally caused by fungal growth.never use outdoor soil or reuse soil from a previous grow.if you must use those types of soils,put them in the oven at 375 for about 20 minutes.that should clear up the fungus.
Depending on the size of your grow room,you will need to install adequate ventilation.also use oscillating fans to keep the air moving.until the seedlings have at least two sets of true leaves keep the CFL at least 10" away from the tops of thyem. hope this helps.