First Time Grower - Indoor AK-47 Clone, looking for advice

I am a first time grower working on growing and harvesting my first plant that I am growing in soil in my closet. However, I am fairly new to the process of indoor growing and was looking for any advice and/or feedback that could help in the growth and care-taking of this plant. I picked up the clone from a Dispensary yesterday and it is currently day 2 in my closet grow-house. Here's my current set-up and pictures will be posted:

The Plant:
An AK-47 clone that is currently ~3ft tall (from the top of the soil to the top of the plant). The date on the ID tag for the plant says 7/19 so I'm assuming it was first planted ~11 weeks ago.

The Location:
The plant is currently in a section of my closet that is 18" deep, 54" tall, and 60" across and is inclosed on three sides by walls lined with white foam board to reflect light. The 4th side is open but there is a black sheet that covers it completely during the dark cycle. The problem with the location is that the closet stays pretty hot (~85 F during the day and ~75 F at night), however it is not very humid. There is only a small window on the opposite side of the closet that doesn't provide very much ventilation, however I do have a fan sitting in the window to bring in cooler air and there is also a tower oscillating fan pointed towards the plant. I am looking for any ideas on how to cool down the closet because I've heard optimal growing temperatures are ~75 F during the day and ~65 F at night.

The Lighting:
New Wave 42: T5 High Output Fluorescent Fixture (47" long x 6" wide x 3.5" deep) with two 46" 54W (total of 108W) Philips Alto Silhouette High Output Lamps. The fixture hangs ~7 inches above the very top of the plant. I got the plant around 6pm yesterday and was told to put it into the 12 light/12 dark cycle so I placed it in a completely dark room until 6am and then turned the HO lamps on all day. However, I was doing research and found that the 12/12 cycle is mainly for flowering and I was thinking of trying to keep it in its vegetative state so it can grow larger before flowering. To do this I have currently left the lights on for 16 hours (the first complete light cycle) and am now going to keep the plant in the 16 light/8 dark cycle. Is this a good idea or is my plant large enough to let it go into its flowering stage. The plant is female and has visible white pistons, forming the characteristic V-shape, at many locations over the plant.

The Soil/The Fertilizer:
Unfortunately we do not know the composition of the soil but the plant is in a 3 gallon pot. Today (day 2) I bought, and used for the first time, liquid plant food that is 8-14-9 and labeled as African Violet Plus food. At the dispensary I was given a packet of roots organics by aurora, Oregonism XL which contains 5% kelp, 25% yucca extract, 3% humic acid and some bacteria. Should I use this instead?

Watering:
I didn't water it at all yesterday (Day 1) as I did not have my set-up completed yet, but today I've watered it twice (about 4 hours apart) with distilled water. The first time I watered it I used 1 quart on the soil and then misted the plant with more distilled water. The second time I watered it I again used 1 quart of distilled water with 7 drops (as directed) of the 8-14-9 plant food. I had been misting the plant intermediately to keep it cool since the closet is so hot.

Complications:
During its first light cycle in its new grow area today (Day 2) several of stems of the more mature leaves turned red colored (I believe indicating a N-P-K deficiency), and also several of the tips (and even some of the edges) of the more mature leaves have turned brown and appear dead. This is occurring from the top to the bottom of the plant. However, the younger leaves are a bright green color and appear healthy. What is going on, and how can it be fixed?

It has been ~28 hours since I've had the plant (12 hours dark followed by 16 hours light) and it has just started its 6 hour dark cycle. I am not completely sure at what point in its life cycle it is at, but I believe its in either pre-flowering or the very early stages. Pictures should be posted and any feedback and advice that you can offer would be greatly appreciated.

I realize that my original post was very long, but i wrote it in great detail in hope of being able to receive the best feedback possible for my set up. However, i understand not wanting to read it all so here is a more condensed version with specific questions.

I have a 3 ft. Ak-47 clone growing in soil in my closet should I let it go into flowering (12/12) or should i try to keep it in vegetative (18/6) for a while longer?

What are recommended fertilizers to use for vegetative and flowering growth? Currently am using some that is 8-14-9.

Are my lights ok for growing in my closet?
They are 108 W 4ft high output fluorescent lights ~7 inches above the plant.

Its really hot in my closet ~80-90 F how can I cool it down/how much do I need to cool it down?

Because it is so hot in the closet do I need to mist the leaves frequently to prevent them from losing too much water through their stomata? Also, how often should i water the plant if it is consistently warm in the closet?

How often should I fertilize the plant? Is it bad to foliar feed the plant with liquid plant food mixed with water?

If the tips of the leaves (mostly on the mature leaves) are brown, as well as some of the edges. What does this mean/how do i fix it? (i assumed it was a nutrient deficiency)

Any feedback would be helpful, thanks.

Ok first of all if there are little popcorn buds like there is on it. Then it is already in flowering. You need to switch the light cycle to 12/12, if you do not then chances are your going to confuse the plant. If you do that it could possibly turn hermaphrodite, or in a worst case scenario go into shock and DIE.

Second of all id recommend getting a high pressure sodium bulb, Atleast a 150 watt bulb. Now you need this because when its in its flowering cycle, which it defiantly is. That type of light puts out an amber color light which is perfect for producing large bulky buds. Trust me the type of lighting you have right now is not enough. You need the right light spectrum. Another thing you need to know is that all HID lights (high pressure sodium, Metal hallide, Ect.) must operate in a specific fixture which contains something called a ballast. A ballast is needed even if its something as small as a 50 watt HPS bulb, Because it ignites the bulb, Remember that absolutely no HID light bulb will work in ANY normal household light socket. It must have a ballast. You should go to lowes or home depot, They sell fixtures that go up to 150watts (which you should get) For under 100 dollars. The 150w fixture is your best bet, because it is cheaper than the 100w fixture remember that. The 150watt fixture costs $52. Now if your only growing one plant, you can pull it off with a 70W fixture. Thats what i have, along with 2 20W cfls, A 120W Dual florescent light fixture, an extra florescent, Plus the 70w hps bulb. And i grow one plant with that. And it is quite effective. If i were you though id go with the 150 watt fixture, because its more power for a better deal. The only reason i didnt get it is cuz they were out of stock. Trust me you need it though......GET IT.

Third for your fertilizers and your temp. Keep using the fertilizer that your using, or get a better on like 10-30-15, or 15-30-15. Just make sure the nitrogen level is lower than the phosperous lever ( which is K on the N-P-K ), for flowering you also want a pretty good ammounty of potassium. Basically start cutting off the nitrogen level, and keep raising the phospherous and potassium levels. Not by too much though. Thats just what they need for flowering. Get a fan to blow on the plant while the lights are on you want the temp in the 65-80 degree range, no lower than 60 but no higher than 80. Also if you use a fan the stem on your plant will become much thicker and stronger.

If you do all that i just told you, i can 99.9% gurantee that you will turn out with a good crop. Its the less costly, but quite effective way to go buddy, Trust me.

Oh and you may want to give it a little less fertilizer, because that looks kinda like a nitrogen burn, on yer tips. Its better to use less than to use too much. If you use to much alot of bad shit can happen to the plant First signs of that would be yellowing leaves like yours, if you give it too much it can get growth stunned too so be careful. Ive had plants die partially because of that.

So did you get yer better lights yet?