yellowing tops & brown spots

Hey guys, so i got some clones that are 2 and a half weeks old and the the tops are starting to yellow. I had trouble in the beginning with a lil too much light and cold temps so they already had some yellowing. Now it looks like the tips are yellowing. Temps around 73, 50% humidity and the light is hlg bspec 135 turned to 20% about 35 inches away.. Also, in the flowering tent I have 2 CK's that are in their second week of flowering and I noticed they have some brown spots on the bottom/middle mature leaves. It's only on like 4 leaves on each. I gave them some cal mag yesterday. Just looking for a lil reassurance on my diagnosis. Hopefully I wasn't wrong haha. Anyways, any advice on either would be greatly appreciated! Oh, here's my grow journal for more info if needed or just to check out! https://www.rollitup.org/t/lazypotheads-4x4-critical-kush-geekbeast-grow.1045663/

Anybody know what's going on with my clones? Their looking worse every day Should I take new clones and throw these?

Okay so the clones are doing better but I still have these spots on 2 of my plants and it looks like another one is starting to get it too. I gave them some calmag the past 2 waterings and it doesn't seem like it's helping. Any suggestions? Oh and thylay smudge looking spot is from me running it to see if any of the brown came off, none did. Started on the bottom and missed the middle but progressed to the top.

When you are in a little tiny cup like that and it’s root bound things can happen. Pull one out and see what the roots look like.

The clones are starting to bounce back. The new growth looks good. I'm pretty sure the soil I used was just too much for them at first. Any thoughts on what would cause the brown spots on my flowering girls?