5k watt garden small air buds :P

I built a stadium grow and placed 90 plants on it with 2 1k hps .... The stadium it 8ft and each section is 2.5 ft wide with 2f inbetween each set ..
had a 12 inch inline fan drawing fresh air in the room and veting out the roof... this room is in 2 weeks of bud and hairs are just starting to show.......

the problem i have is i got 6ft plants in the other room that where fliped when they where 4ft tall never topped and they are min the 5th week of flowering and there really not filling out ... i have 4 different strains afgan kush / widow kush ( which buds are long around 2ft in lenth with tight inter nodes but the nug is airy and loose I have light fairy close never more then 2 ft away .. I wanted to kwno whats causing them to not pack on the weight what might be some factors?

the last crop was the worse crop i ever grew unknown strain and it was teribly same airy nug that amounted to nothing had 6 plants finished at 3 feet tall in dwc kept ppm at around 12-1400 and ph at 5.8-60 with no ventilation temps got high at time mid 80's never higher and all under a 1k hps and only yeilded 6 ozs absolutly terrible ive goten 2lbs off an aeroponic table 4x8 with 40 sites under 3 400 hps befor with buds the size of 2l pop bottles but lately i invested 6k in to gorwing and cant get a yeid worth talking bout what could be the matter?

lights on/off temp fluctuations to large

Im gonna say it since noone else is... Your at most 5 weeks in on whats probably a 13week strain. 2 feet away is a bit far from my experience but for a 1000w its probably alright.

Just reread and you do know that flowering isnt when you switch to 12/12 but when you actually start budding. Yiur second room isnt 2 weeks into budding if your just starting to see hairs its in the first week, you cannot count from light switching