Need a second opinion on these small yellow spots on fan leaves

-Running an indoor hydro setup in a small tent
-Hydro balls in a 5 gallon reservoir
-I change the water weekly
-Following Technafloras Recipe for Success
-Plants are in veg under just a 250 MH
-PH 6.5-7.5 (I check twice a day with drip test)

This is only my second grow. I have 6 pots but only had 3 cuts the first run. This time around I have 5 (one didn't take too good to the transplanting but the others were great). All the strains are different.

So I've been searching and searching the web and looking at photos but I think I'd benefit from an experienced grower opinion on what this is, should I be worried, etc.
About 2 days ago I noticed yellow spots on one of my plants, and yesterday I noticed the other plants were experiencing something similar.
I don't know if it's the lights, I doubt it because I'm also housing my roommates clones but they are in their own seperate pots and seem unaffected. Oddly enough though they came into my room the day before the yellow spots starting to appear. That same day they were put in however, I also changed the water and replenished the nutrients.
I have yet to ask but I want to ask my roommate if he ever had these cuts in his room downstairs because he did have a spider mite problem a while back but if he just picked up his babies from the shop and brought them here then that eliminates that possibility. I'm going to take a magnifying glass and take a closer look later today.

When I first noticed a spot on my Alien OG it was brown and soft (the spot itself) the next day the spot was yellow and more on the crispy side, and then I noticed them on other plants. The shorter clones have same thing going on but mostly leaf tips I think.

Anyways here are some photos (NOTE: Shiny leaves are due to a dose of an organic mildew fungicide I use as preventative)

I'd use a new PM treatment if I was you first of all.

Check the bottom of your leaves just in case but it doesn't look like bugs. White paper underneath, shake it, see if you find any.

I think phosphorous off the top of my head, but your pH is way out man. 5.7 and let it drift to about 6.5 and bring it back down. Never as high as 7.5. There's your problem, it hits the high end and is probably locking something out.

it had been at 5.7-6.5 ish till yesterday and I was told by a friend to try higher ph and that it looked yellow but I'll adjust that back.

New PM treatment?

Powdery mildew... whatever you're spraying as a preventative could be what I'm seeing but I definitely think I see real white blotches underneath it on leaves. I would just get some clean clones if I was you to avoid problems throughout, but that's me. But yeah the pH is way high and bring it down, make sure it doesn't drift too much and then I'd say just follow the feed water water advice technaflora gives. I remember having deficiencies using their system in hydro too, but, it produced AWESOME bud.

*sigh* I got powdery mildew my last grow and have since wiped down my tent and reservoir with bleach but I'm guessing not thoroughly enough. I used this same PM treatment last grow however and after I had found some real powdery mildew. Its a once a week treatment that made it so I never saw it again so I think I'm trusting it. I just gave it its first spray last night thinking it was preventative but maybe the mildew already got a hold AKA could be a neglect on my part. I'm a bit paranoid of my room mates clones as they are in rock wool and retain a lot of moisture and he's yet to cover it. . .

I have no way of getting a whole new set of clones :/ but I'll keep an eye out for the mildew. You have a better treatment that you recommend in the event that mines really not working??

stop foliar feeding so much. and just keep the humidity down.

I actually don't foliar feed at all unless you count the recent natural PM fungicide? But I just started using this last night while the spots have been since 2 days ago.
And I'm pretty sure humidity is ok. I've got a fan, intake duct and also keep vents w/ screens open on the tent and keep my windows wide open. I live in the Bay and the weather is beautiful and breezy so they get fresh air coming thru there too. Also, tent is in a corner that never has any sunlight hit so all the breeze and none of the heat (if any, doesn't get too hot here).

Oh I also wanted to say YES I hear a lot of the same things about Technaflora, weird issues but GREAT turn out.

don't overanalyze. its mostly healthy leave it be