"1 Random bag seed" Thats the problem. People think that a seed from a good bud will be the same but they forget it was most likely knocked up by the crap male and those seeds only produce crap, problem, Hermite, plants. Your growing may be fine just need to get good stock then see.
1 1000watt HID would cover it but two 600 watts would do nice in there if you got the cash for both lights. Depends no what lights you use as to what fans to get. I run a 750CFM fan and love it.
what can you get your hands on? Lime is the best and fastest, and i just got mine at wall mart. any feed stoor will have it too. Or you can use ashes, wood chips. peat moss, ect.
When i water i do it in two times 5 min apart. That way the soil has time to expand before the next drink and there wont be any dry pockets in the soil.
Are you in soil? If so the soil will buffer the ph its self by the time you need to water again. And changing the PH to much at one time (dramatic swings) will cause more problems than it fixes.
Theres a book on training techniques in here. and if you want to do organics then read TOL by the rev.
https://www.rollitup.org/Journal/mike4c4.764086/