First Grow need help

Hey, its my first grow and I made a hydro box from a 40 gal plastic rubber maid, purchased all the nutes and ph up and down, and have a 400 watt hps light about 40 inches above the rubber maid. I planted two seeds which sprouted nicely in two net pots filled with hydro-ton and set the ph of the water around 5.5 - 6 ( cant tell since im using strips) and added some nutes according to the labels on the back of the bottles, but after 7 or so days the tips of the bottom leaves began to turn a yellow/brownish color, and my top two leaves started curling inwards (which got me to post this). So I added more ventilation with a bigger fan, but its in a closet ( about 5 1/2 by 5 ft) so it heats up real easy, 75 F +

Can anyone help me, its my first grow, and I've basically learned everything of forums and friends. Any help or advice would be greatly appreciated.

If pics could help I add them tomorrow, just gotta buy a camera.
Also...

And after reading some forums and watching some vids I saw that people normally use florescent lights for the seedlings instead of the huge 400watt hps bulbs so I wanted to know what kinds of lights to use on the seedlings

and is it alright that I grew the seedling directly in the hydroton, they sprouted nicely, but it took them all three to four days.

i like your dedication...........just gotta buy a camera........lol............

I hope these photos help, I thought that the growth was stunned from the heat of the hps light, but from last night it showed a little growth...I would appreciate any help or advice on what to do with her

I also though she might of had a phosphorous def, but could be wrong .. thx for the help

cant see the pics

somebody tell em how to make the pics work

sorry imageshack is a bitch so i uploaded them

how old is it? could be nute burn and as far as lights your good but it's best to use a light with a blue spectrum such as a MH( Metal Halide) while veg but I don't think the spectrum would do that...

just get a conversion bulb:
http://htgsupply.com/Product-GrowBright-400-Watt-MH-Conversion-Bulb.asp
or T5 i heard are very good but not better than HID lights

Too much Nutrients you should still be using 1/4 strength at that age

Thats what I thought the problem was, so should I dilute the water in the hydro box with clean water or should I replace the water in the box and add a fourth of the nutes of what the label on the back of the nute bottle says to add?

And my leaves are also curving inwards, which I read usually means there trying to conserve moisture. I water them three times a day manually with the water in the hydro box, which i think is a mistake, but my friend tells me thats the best idea.
Any thoughts?

And btw
Thanks a lot, I really appreciate the help and advice, didn't know how helpful people were on these things

I would replace the rez with pure water wait 2-3 days then add 1/4 strength. change your water every week, some people do every 2 weeks. next water change go up to 1/2 strength . then next water change go full strength.

and remember if your plants drink too much water only add water. NO NUTES. only add nutes when you do your water changes.

let me restate the water changes. when your plant is little it wont drink the nutes as fast so you may let it go for two weeks before changing water. but since your not at full strength yet i would change it every week and step up the nutes until you reach full strength.

thanks im cleaning it out right now

no problem

Does anyone know what the proper ppm should be a 13 - 14 day old seedling/plant in veg?