[19Purpleking69]

Hey all, I'm new to the growing scene but not new to life. I have a pretty good set up that's been holding 84 degrees and 60% or less humidity with lights on and around 70/52 with lights off. I used Fox Farm Ocean Green soil with perlite when I transferred my young girls from cup to 2 gallon pot. I didn't add fine dolomite or Cal-Mag or anything else to the soil like I later found out I should have. I have 8 6"-8" girls growing under 1-400 watt HPS air-cooled hood that's vented out of the room with an exhaust fan. My cool air is brought in from outside of the room with an inline fan and aimed towards the ground. I also have 2 small fans inside moving air around. My room is 8X8X6.5 . Well insulated I think.
I've chosen to use Canna Substra veg in the 2 part mix and a General Hydroponics root stimulator during veg. The girls aren't very big yet and they have just had their first real feeding. They are about a month old. They had some stress in the first 2 weeks until I got my room better together. I didn't have the root stimulator, PH down or Cal-Mag when I first feed them but my cheap 3 pronged meter said the PH was just below 7 . I don't have a good PH meter yet. 1 of the girls also had spider mites, visible webs, when I got her. I took care of that with some neem oil spray rubbed gently into the leaves, all girls got the neem even if I didn't see mites or webs. Better safe than sorry.
I also changed my light set up 2 times since I've had the girls. From 2-125 watt CFLs to a 400 watt HPS bulb with a cheap reflective hood. Then to an air-cooled better reflective hood. In the last week I also added a 6" inline fan to bring in fresh, cool air from the basement. I still need some sort of a filter on the outside of the inline fan to filter any crap from the basement from getting in my room. No rush on that yet, still warm weather here.
I noticed the day I was going to feed them for the first time since they recovered from the stress that there are some rusty colored blotches forming on some of the leaves. They didn't have any nutes since they went from lite greenish to almost hunter green so I know it's not too much nutes. I think it's low on Mag/Cal so I'm either going to get some Cal-Mag or some Epsom salt. Any suggestions? I also plan on building a movable wall inside the room because I'm only using less than half of the room at this moment. Although, the temp is good now so if I made the room smaller it would maybe make the room hotter which I don't want. I had to fine tune the light/fan schedule this morning because I think 1 of my timers is out of sync by about 15 minutes. The light was on and no exhaust fan blowing and the temp got up to 87 degrees for about 10 minutes.
I'm looking for good advice. I'm on a budget so suggesting the most expensive stuff is out of the question for now. I know I need 1 more thing to add to my veg mix schedule, not sure what I should get though.