Lost and dazed.............

Im new at this whole thing. I have 3 plants in the works. 2 are just sprouting and the 3rd is about 12-14 inches high. I've noticed the bottom leafs turning yellow and there brittle to the touch. Im having new leafs coming into play at the top and i've been giving it 24hrs of lite a day. Is that good?

Like i said im a newbie so be easy on me ehhhh

Hank.

Are the bottom leaves round and smooth?

Nutrient def!
Most likely, I had the same problem.
Pics would really help us out.

WOAH! Don't scream nute deficiency without pictures and some more info. What kind of soil are you using? What kind of nutes have you given them? How much? How long have the been growing? If you are in soil and you fed them with just water, they would grow and not show horrible signs of nute def., so I'm weary about crying that one out for fear you will add nutes to a plant that is nute burned.

Most likely causes at this stage are TOO much nutrient or overwatering. Could be mites, but really need pictures to determine. Don't do anything hasty.