baby plants turning yellow, please help

ive started growing about eight plants and they are about 4 inches in hieght and the leaves are turning yellow. three plants are doing fine but the rest are turning yellow, they dont have brown spots or brown tips. i dont really know what to do because its my first time growing. i havnt used any fertilizer yet and i let my water sit for like a week before using it to water the plants, please help it will be much appreciated i dont want these little guys to die i only want two plants for budding but i dont want any males so that is why i planted so many.

THX

ps- started from seed

Well you have giving no real information to be able to help you.

How are you groing hydro/soil?
are you using lights? if so what kind?
Are you growing indoors or outdoors?
What are you temperatures.

Give us something to go by to be able to help you.

Yellow leaves at an this early stage can be many things

We are not mind readers and cannot see your problems without pictures

SO the more information you give us the more we will be able to assist you.

With nothing we can give nothing.

Firstly - assume you'll get 4 females 4 males (ish...)

secondly - how old are they? (Yellow leaves is usually a sign of lack of nitrogen - is it time to start feeding? Usually around week 3-4 when the very first leaves die is when to start with nutrients...)

sorry guy new at this. im growing in soil under a few flouresant tubes. indoors i live in canada so its like -10 outside, ihave one flouresant plant and aquarium wide spec. two foot and one cool white 18 inch but i dont think its wide spec and a cfl 13w i just got fertilizer s if it needs to be fed i can do that the soil is just some soil i got from wal mart premium all purpose moisture mix.its actually quite warm in the room, like 80degrees F. the largest of the plants is about three weeks, its wierd cause some are doin fine others not so good. thanks for your help

Big question... ARE YOU PH-ing YOUR WATER?

Rainwaters good for plants...SLIGHTLY acidic - actually round here in the uk the waters pretty much fine, 1 drop of vinegar to a litre sorts it out...get yerself a cheap PH tester on ebay