First time grower PLEASE HELP...

i need help... i have a white widow clone from the club an the leaves are aalll looking fine except the biggest one its about 70 percent yellow and the rest is quickly turning yellow... i have never grown before and dont really know what i am doing i need help... i put my plant under a light more than i put it in the dark. and i water it with regular house water every 3-4 days. help?

http://i44.photobucket.com/albums/f36/bamsk8r014/01-11-08_1550.jpg

http://i44.photobucket.com/albums/f36/bamsk8r014/01-11-08_1551.jpg

http://i44.photobucket.com/albums/f36/bamsk8r014/01-11-08_1552.jpg

these are pictures of my plant its only about 4-5 weeks maybe more i honestly dont know.

got any pics yama??? you'll have an easier time getting help if you can "help me help you" (Jerry mcguire) but seriously, get some pics... then you'll prolly get some help easier..
E.F.

holy crap that was fast!!!
soooo.... nevermind about the last post I'll look at them now..

ok buddy u need to i guess get some real good soil and make sure it doesnt have fertilizer in it. then get some fertilizer. i use general hydroponics 3 part system i think its call flo grow flora bloom and flora micro anyway u need to follow the directions use 1/4 the recommend dose they have on there for clones & seedlings. keep it under a couple of bright daylight cfls 24 hours a day or no less thatn 18 hours a day if you dont want to do 24. then u should be able to save its life.

dont over water cuz u want air in the soil too for the plants roots to breath

after that I would read up on the above growfaq and reccomend you get a good 400watt hps light. thats if your planting to grow your own stuff.

www.htgsupply.com has ones as cheap as $116 and that light will grow u mondo buds.

good luck and god speed. once you master it, tell you friends and your freinds freinds how to do it

hmm.. if you were in the later stages of flowering I would tell you it's no big deal for leaves turning yellow, but honestly I dont know what the problem is.
I do know that watering with "tap water" that is untreated is not advised. I would leave a pail/jug of tap water out for a few days before using it, that way the chlorine would of had time to evaporate. Also, regular tap water will have a ph level of around 7.6 (or so) and ideally, ph level for plants should be around 6.1 - 6.4. Also not knowing what the NPK of your soil is makes it difficult to judge if they have too much or too little nutrients. What type of light are you using??? how long are you running it???
There is a lot of info on this site, Id suggest you get reading. Youll get lots of help but you need to be prepared with at least some knowledge.

E.F.