1st grow, DIY setup with CFLs, need help

Hello, first of all thanks a ton to everyone in this forum ive learned so much info from the newbie threads. I am a low budget first time grower myself. I have 4 seedlings. At first, i didnt have any set up at all, i was just putting those seedlings under 15w warm CFL (i was thinking like what the hell it is just a plant it should grow out like every other small indoor plants then i made a lot of research and find out it needs a lot of things and most of all it needs a lot of gardeners attention. By the time i have plans about the setup, seedlings kept strecthing and falling down one by one. It took me 1 and half months to set a DIY setup. I transplanted the most healty looking ones and buried their stems so that it will become shorter. Now i got 4 of them and its been 2 weeks since ive started to taking care of em. My setup is
-cardboard box (20"x25"x20")
-130W,6500k CFL, 2x100W 6500k CFL (those wattages are equivalent values not the real ones) (17/9 for 1,5 weeks but now ive turned to 24/0 since few days and its like 1 inch to the plants)
-peat (soil formed of dead but not fully decayed plants found in bog areas, which should have some food for the plant in it i assume)
-Temp. is room temperature.
-PH should be around 6, i didnt nuted or anything yet, i give em regular drinking water in room temp. it shouldnt get acidic or alkaline.
-Moisture is normal since its not in some place like basement or garage and the climate is not really dry or wet in this part of the world.

Ever since i start to take care of them, they started to grow some leafs and looked healtier but few days ago, the cotyledons turned yellow and brownish and in the following 1-2 days, 2 most grown ones started to pale ( leaves started to curl up a little and there are some purplish parts in the front edge of the leaf ) the general color tone is going yellow. It would be a lot more easier to diagnose with the pictures of course, i will try to upload some. Shall i start feeding? What kind of food? In what frequency? Where am i going wrong? Please feel free to write any kind of suggestion or criticism. Oh by the way, ive seen some pictures of a 2 months old plants from the seed and mines are looking like 1 week old seedlings with 4-6 small leaf. Thanks in advance.
Peace

I dont see your growing soil mentioned. If you are growing in straight peat you need to repot them immediately into a nice potting soil.. Like Miracle Grow or some cheaper version. Peat Mosss has zero nutrients, Ancient people used peat moss to preserve foods in! You can add nutes, but all the other essential stuff wont be there. Personally I give mine rain water in wioth the tap water. Sounds like your on your way otherwise. You may get a little cramped for space. You might want to line box with mylar (Emergency blanket in Walmart camping section) or alum. foil. Blanket is probably cheaper.

I just realized that peat doesnt have nutrients at all like you mentioned. Do you think it might be the case with leafs turning brighter green and purple in the edges? I also noticed i would most likely be out of space if all of the plants survive and grow like it should though im able to change the box at any time so it shouldnt be problem, plus i dont expect all of them to grow female, it was just a rondom seed afterall. About the reflection and light issue, i use alum. foil but it seems inefficient somehow. What do you think about the CFLs that i use? do you think it would be enough for vegging 4 plants until showing their gender? Is it ok for those cotyledons to fall off? Thanks for the comment.

Yeah I would transplant to potting soil as soon as I could. The lighting is most likely alright but I personally would like a couple of more. Your not having any heat issues or anything? Dont worry about too many plants, some of em are gonna be males most likely. I got 1 female out of 5! Maybe you get luck, i hope you do! Dont worry about them lower leaves.