newbie with an array of minor problems and one big one

Your Equipment:
.1) Type and wattage of lights. 5 23 watt cfls 4 plants 1 seedling setup as a square with one down through the middle.
.2) Distance from tops? a bit over 3"
.3) Reflector type? 4 main lights have individual bowl style reflectors middle bulb open
.4) Is there a consistent fresh air supply?yes
.5) Do you have an exhaust fan and a circulation fan? circulation
.6) What are the bulb wattages, kelvin ratings, and schedule? 6500k, schedule I'm assuming is time..24/0

Your medium:
.7) Specific brand and type of soil? was a local "high caliber" growers mix...not very good extremely rich and kind of like mulch. As of last week Fox Farm Ocean Floor nothing added
.8) Size of container. 1 gallons
.9) Did you use peat pucks (or similar) to root clones or germinate seedlings? no, paper towel germination

Your nutrients and water:
10) Source of water? (tap, bottled or filtered) What's it's ph before adjusting?tap(boiled for 20 min then cooled) ph before adjusting off the charts so we will say 8.5
11) Method of checking water ph. GH test kit
12) Method of adjusting water ph. Gh acid & base
13) Specific brand and N-P-K ratio for each bottle. not feeding right now. fed on with MG big oops. that was week 2 this is week 4
14) How often are you watering between feedings, and how much per watering? varries but i water about every 4-6 days when the only moisture i can feel in the pot is down past my last knuckle then i water enough to barely trickle out to test ph
15) Any additives or tea's? no
16) Are your ph levels stable, or do they fluctuate?only been testing for 2 waterings but stable.
17) What is your ingoing water's ph? ...your runoff ph? ingoing 7.0 runoff is about a 6.3
18) Do you foliar feed? no

Your growroom:
19) Indoors or outdoors?in
20) What size of closet, room or hut? closet 4Lx2Dx9H
21) What are the temps and humidity levels while lights are on? 76F no humidity check
22) Have you seen signs of insects in the growroom?only the occasional fly but i would assume that it trails in behind me

Your strain:
23) What strain are you growing? n/a
24) From seeds or clones?seeds
25) Is this an autoflower strain?n/a
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So heres my dilemma. I have one plant that has the looks of literally every problem possible that is the most specific I can be there. The other three are for the most part looking good since the repotting and beginning to ph the water. A common issue between the "good" three is yellowing tips and edges and which then goes in between the veins and starts to turn into brown spots. this is on old growth but even new growth has yellow tips. All have been FIM'd except the one that got MG and are still growing like crazy. So i have not noticed a stunted growth but this is also my first shot. With all that said I am also looking for advice on anything you want to throw out for the future, nutes, lights, trimming i am a sponge.