Why are Leaftips Yellow?

[Swift420]

My plant is about 15days old. I water it around 3days. light schedule is 18 hrs 250HPS bulb. with a sun system ballast. i just took a quick look at her and the edges of the leaf are looking like they are dried up, dead. or yellow, does anyone have an answer to this problem?

[tetrahydrocanna]

pic would help...

[guy from 70's]

check your temps.....keep it under 80 at the plant level.

if your using nutes....stop....flush with water....an water every 4-6 days..your plants are pretty young an may not tolerate nutes yet.

if your temps are high.....either add fans OR use a glass shelf under your light as a heat sink.

I was having the same problem with heat....Im also running 250HPS in 2 square feet.
I put two glass shelves under the light and my temps went from almost 100 at plant level to 76-80....things are fine now...

[Swift420]

PIC WOULD HELP!!! Want to know why I dont hav a picture!? ASK THE FUCING GEORGIA STATE POLICE. I was driving to FLorida from North Carolina and I was doing 18 over. Trying to make good time and was excited to see palm tree's. Next thing I know I'm in the back of the car listenen to rap ( the cop liked rap and was blasting it ) while him and 3 other pigs and a dog search my car and find a half ounce of killa. Zero Tolerance in Georgia, so I am taken to jail and spent two nights in a cell block with other inmates who are in there for Counterfiet or Meth Manufacturing. The cops got my camera talken about their's evidence on here. I had pictures of Ounces and plants and shit. Then they said when I leave I can have it back, but it was locked in the evidence room. My lawyer is getting it back for me though, but I wont be able to take a picture until it comes back.

I AM NOT USING NUTES. And It doesnt feel like it's that hot in my closet. But Maybe it is the heat. The fan in there I had shorted out and stopped working but since the plants are so young I figureed they dont need it. But thanks for the help you all, I will try to salavge them before they die.
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EDIT:
I just repotted the plants so hopefully the fresh soil will help them, althought I fucked up a few roots from the biggest plant. I hope this works. Controlling the tempature I am uneasy on doing, I have the plants about 2.5ft from the 250Watt HPS bulb, so maybe I should increase the distance from light to plant?