plants are dieing?!

aight so i made a little grow box for me, and i have a 70w hps, and 2 floresents in the box, all the plants are getting plenty of light and fresh air, with all the water they need, but after about 3 weeks the leafs start to point down and the tips start to turn brown and little borwn dots apper on them... i have no idea what the problem is, 2 of them are in a hydroponics system i made, and it happends to them first cuz they grow faster...

so plz can anybody help me save me crop... here are some pics, thanks

the only problem i get it is the tempature gets around 80 and stays there, only cuz my fan keeps it around that tempature, without my fan it would get to 90ish

yea sounds like a heat problem.. that shit happened to me and fucked my first crop.. ended up with bugs and shity result.... try to get the temp dow to 72 to 76... potable air conditer, leave the door open on ur box, etc u just got to figure it out... how big is your box?

the box looks like a cut in half refigurator on its side... and they cant be drowing because its the hydroponic plant thats dying... but soon the soil plants will turn out the same... any other ideas on how to cool them down... a cheap way... curently i leave all the doors open and the fan on 24/7.. if it is a heat problem then any ideas how to cool them without spending alot of money?

thnks

I doubt its heat, well just judging by some outdoor's i've seen in 100+ fine.
But they were bigger... i would also chill with the watering, let them breathe.

Over watered and overfed,let them dry out plants need oxygen in their roots and you've basically drowned them by the look of it

alight, but how do i let the hydroponic plants dry out? if there roots are constently in water? all i could stop doing with them is stop spraying them right?

They're not supposed to be in water constantly. You're supposed to have some kind of system set up to pump water in at regular intervals, and then let it drain out and be dry for a while.

Hydroponic growing does not equal throwing seeds in a pond.

oh, alright... so tell me if this would work... right now i have a contaner with the nutriant solution and and air stone constently pumping air in the solution and the plant being grown in a contaner with holes at the bottom for the roots to go into the nutriant solution... so wat if i keep the plant roots in the solution for a day then in an empty container for the next day, and so on? would that work? if that makes sence?...

but thanks for all the help, its greatly appreciated