Brown Tips, Using No Nutes

i dunno if this is a problem or not, i'm not worried about it till i test the ph of my soil. i was just seeing if anyone could give me a head up on this..

the temp is 80ish, using 4 26watt cfl's and one 30watt, they are like 4-5inches above the plants. i'm using a miracle grow soil.

maybe a bit warm...80...try 70
that soil would have nuts added so you prob don't need to feed any for a few weeks....

Maybe try and get the humidity up, and like jats said lower the heat a ltle.

80 isn't too hot at all. perfectly acceptable, not OPTIMAL, but perfectly healthy, measure heat with the bulb of the thermometer acting as a leaf... that is set up your thermometer so it's the same height as the top leaves getting direct light from the lights, i bet it's over 90.

what kind of MG soil are you using, moisture control? if so your plants are overwatered. if you are using standard MG potting soil your issue is nute burn. (so if you're using either of these two soils transplant ASAP and flush. if you are using MG organic your issue is undoubtedly heat or possibly pH, but it's a little early to have pH problems.

that's the prob with mg soil, it' meant for adult plants, and it's kind of overnuted for cannabis... if you've been fertilizing on top of this it's even more of an issue. no nutes whatsoever (besides organic nutes i.e. shit and castings) for the first 3 weeks.

If you are using organic then just Water with distilled PH balanced water only for a week or so.
You may want to keep some water around because it sounds to me like you have more nutes then you need.