Help! Really pale green new young leaves!

Hi,

This is my first grow, i'm growing under 5 30w CFL in Australia, every morning i wake up, take the plants outside where they get natural sunlight, then just before it gets dark i put them back under the lights inside, all inclusive they're on a 18/6 light cycle.

As you can kinda see in the photos, the new leaves are sprouting, and they are an extremely pale green, virtually yellow color, and some of the older leaves have some necrosis as you can also see in the photos, any advice would be more than appreciated!

What medium are they in? have you fertilized? What strains? Need a little more info, but it looks like nitrogen deficient, but it could be many probs. We'll figure it out with more details. Btw, foil really doesn't work well, it can actually cause hot spots and harm leaves.
Peace,
philfish

They are in an organic soil, which i later found out is enriched with fertilizer, not sure as to the strain (in australia, can't buy seeds over the net) I have a feeling it might have been because i overfertilized (with the enriched soil) and PH went too high, i have since transplanted into fresh soil, just added neutral water, and going to wait and see how it goes.