possible nute burn?

these plants have been in 5gal buckets for about 10 days now, they where transplanted as soon as they sprouted, they are under a 600w hps in a 1.2x1.2x2m tent. temp is 80 rh 45% I noticed curling of the leafs a few days ago and was told not to worry about it but the plant that was causing the most worry has started to get a bit worse and the bottom leafs arnt looking to great

the leafs curling like that are probably from heat. its not a big deal, but keep the heat in check.

any ideas on the bottom leafs in the first pic? thanks

Except for the spots they're looking healthy -- what are you feeding? What are your ppms/ph?

Im using ionic grow, rootbastic and just started using liquid silicon today. started them in the buckets at 350ppm and just raised it to 500 today. ph at 5.8. after raising the nutes today ive been freaking out incase it might be to high a ppm that is causing the spots on the leafs :0 I have just started using the ionic at about 1/3 strength now, about 80% for both rootbastic and silicon. thanks

I don't know anything about those nutes in particular. You ppms might be a smidge high. At 2-3 weeks, 300ppm would be just about right, 4 weeks (400), 5 weeks (500) up to 8 weeks, then hold at 800 ppm for flowering. At least that's the way I do it. I have just a basic 3-part nutes kit from Advanced Nutrients, and I add cal/mag as the ppm of my water is a little low (140) and therefore I'm a little light on the cal/mag from the water.

Since the plants look healthy otherwise, why don't you back off the ppms to 300 for a couple of days and see if that doesn't stop the spreading of the spots. If no new spots develop, then it might have been over-feeding. If the spots continue to spread, then it's something else. The spots you have won't get better -- they'll stay the same even when you fix the problem. But the problem won't continue to new leaves.

il give that a try thanks, the ppm of my water straight out the tap is about 280. I was told that when adding nutes that you consider that as zero and deduct it from you ppm once you add the nutes to get the true ppm, is this correct because if not my nutes are currently sitting at 780 thanks.