1st time grow - 2.5 weeks in. Can I get some feedback and advice?

Hi,
This is my first grow. I've had some problems with yellow discoloring on the new leaves starting in the middle, which I think was sulfur deficiency. I added some epsom salts and it seemed to do the trick. The plants recovered but the new leaves are still a light green. Is that normal?? Also, I have a 24" H X 16W box. How many plants can I grow hydroponically to about 12 - 14 inches with a 1.5g resevoir? I'm looking for 1 - 2 oz yield per plant. The box runs between at about 85F - 90F and mostly 30% humidity. I'm using Miracle grow but am switching to FoxFarm and add 1/4 cup every 4 days. The plants pictured are about 2 1/2 weeks old. Should they be bigger? And there's some yellow/brown spots. Should I be worried that might be nute burn? The box set up is currently 2 X 6500 CFL and 1 100w CFL (I broke one of the 6500's and replaced it with a CFL I had lying around - don't have those specs).

This forum's always been really helpful and I appreciate the support. I really want to take the time to learn how to do this well.

The light colored leaves seems to be a sign of N deficiency, you should also lower you lamps so your plants won't stretch.

Thanks. I'm trying to get a Ph tester but every Home Depot I go to doesn't carry them this time of year. The lights are on a power strip so they're fixed there. I got the box on Ebay, didn't make it, otherwise I would have had them on a chain. I had them on a shoe box to keep them closer to the light (at the bottom of the box they get about 500 lumens). Thanks for the help and please keep the feedback coming. I'm trying to learn as I go.