Hey I got my 25day old plants under my 400w hps a bit more than 2 feet away. Problem is its been gettin quite hot it even got up tp 31degrees celsius...Is this a problem? How far away should the light be?
well by 4 weeks your girls should be atleast 15-20 inches your light should be 1 foot from the tops, make sure you have goooooood ventilation and air flow this is crucial and heat is a major thing, hope this helps
u can just leave the door open when the light is on the lamp doesnt produce so much heat and if u have an open window the temps will get a lot lower. i just finished my 400w grow with no vent and the result is pretty good better than average weed on the market now which is fine for me