HELP!!! my leaves are dying !!!!

hi im new at growing i just bought 3 clones 2 days ago wen i got them they had some leaves that looked like they were dying but i took them off today but most of them were all nice and heathy i transplanted them yesterday from small red pixie cups into bigger pots and new fresh mg moisture control potting soil mix i have them all under a sunlite 42w 120v Fluorescent lightbulb about 12in above top of plants i leave it on 24/7 my ph is about 6.5 temp day 80 night 78 i spray them with water about twice a day i have a mini fan blowing air in and a fan blowing sucking air out im really worried about them.......any tips out there???? anyone expierance out there???? im open to any advice

Is your light a propper light for growing? is it a fluorescent light? . 12 inches away is abit too far away if it is a fluorescent. You need to be abit more specific when you say your leaves are dying. What do they look like? can you post a picture

yeah the box said it was for growing it was my friends bulb before and he used it for growin also........well the tip of my leaves start yellowing and sooner or later the whole leaf is yellow or a very light green im scared its gonna end up killing them completly.r...im gonna try to post pics.......how close do you think i should keep the light from the top of the plants?