I have got Super Skunk plant doing the same thing, also went through this recently with my last run of Northern lights. I believe that it's Nitogen Toxicity. Why?
My last grow consisted of 21 northern lights in MG soil. I was adding Alaska fish food 2 times a week, it did the same as you stated...
I thought of doing the same thing under a 1000w hps, almost everyone I spoke to say bigger pots fewer plants works best. I use 3 gal. pickle buckets My buddy gets for me from his restaurant, they are nice and square and fit tightly together under light setup.
I think as long as there is cool air circulating you'll be fine. Temperatures will fluctuate a few degrees here and there but shouldn't be a problem. How are they now?
I used 4 85w 5000k spirallies to move around under my 2-T5s that had 2700k 4 foot bulbs seem to work ok. 2700k is best for the majority of bulbs during flowering. Just do your best and learn from each experience. I use a journal to note things from each grow.
I cracked some Super Skunk and OG Kush seeds under a 4 bulb 54w T5 and they exploded. LEDs work well I hear also. I grow monster yields outside but am trying to find the perfect Cfl setup..
I have 2 4 foot T5s with 54w 2700k for flowering. Would it be wise to pu newly rooted clones in gallon pots under these? How many? How mouth to expect? Also have 4 100w spiral bulbs to move around underneath. Thanks.