need help

hi every one im a first time grower got 4 plants on the go under 400w hps in bio bizz all mix soil there about ten days old one of them has a yellow patch on one of the leaves. temp is about 23-26 and humidity 40-50 do you think it could be overwatering

lookes like over water to me bro,get them in bigger pots and only water if it fells dry 3"-4" inches down in the soil.

Hope that helps.

how faraway are you runing light heat strees or over kill on water feed looking at the size of plant will only need water about every 3 days

wat welshie said, heat stress and over watered,

thanks guys. here is a couple more pics of the others do you think they look okay. my 400w hps is about 18inch away from the plants do you think i should put it further away. another thing didnt think i would have to transplant to bigger pots so soon they have only been in them pots 10-12 days

I'd move the lights off them some more. Go close to 30. They are little guys (well, hopefully gals!). Once they get a bit bigger then drop the lamp closer.
(just my 2 pence)

yea my new cuttings had the same problem the light is zappin more out of them , than they can handle, but now there doing fine the lamp is closer and they are booom,ing groth like mad very close internodes 6 leaves groing at once