My First Hydroponic Grow

Hey All!
As an avid pothead, I have always had thoughts of growing swirling in the back of my mind. The other day, I was given a sign from god that I should start my very own grow setup!
In the garbage near my house I found a fully fiunctional aerogarden, and as of june 6th, I have begun growing.
A few questions:
1 Should I be concerned about pH levels this early on? I haven't done any readings yet
2 I'm currently running on 20h on 4h off, is this a good cycle for growth/ veg?
3 One of my plants is begining to show yellow on the ends of the leaves, thoughts?
4 I am currently growing in all 7 slots, but from what I'm reading I should max the box out at 4
5 What about raising the lights over time? should I invest in more lights? I have a laptop cooling dock currently as my fan, is this enough?

Finally, what's the ideal conditions for veg? As in pH (I've read thaat 5.7 is ideal), water temperature, and light cycle.

So long post, those are all my questions so far, any and all help is appreciated, I'd post pics but it's currently in the 4 hours of darkness so I don't want to disturb the resting plants.

Thanks!

hey man welcome.. im a novice grower too ~ 40 days in the game, but ill try to answer as best as i can

1- ph is VERY important. i once used normal tap water - which in my area is TOTAL crap and filled with minerals - for about 3-4 days.. my plants started getting really weird black spots - i wasn't checking ph too frequently... i checked once in the morning, and then forgot and checked the next day at night.. and with shitty water - pH fluctuates ALOT. you can adjust it to 5.7 - but in a couple of hours - it COULD be 8. or something similar. and plants HATE drastic ph change. in a 24-hour span you dont want the ph change to exceed 1. what that means if your ph is 5.7 in the morning and you forget to check later, and its 7.0+ or something next time you check it, thats bad. you want to keep it under .5 change in 8 hours or 1 change in 24 hours.. if that makes sense.
whenever i do my weekly resevoir change, i notice that for the first couple days, the ph kinda fluctuates faster - so i have to be monitoring and adjusting it more frequently. but after a while, it just chills at 5.7
basically - yeah dude just check your ph frequently. make sure you keep it between 5.5-6.5. thats the best range for hydro and it is very important

2- im not sure, i got my plants as clones - and i went straight to veg cycle. i use 18-6. i think 20-4 isn't too bad, but might be a little stress.. not sure tho

3- not too sure

4- yeah dude the ag res is very small. its only about a gallon or 2 and thats the expensive models, 100+
i got the 50$ model and it was like.. half a gallon? lol
right now, i got a custom 4 gallon reservoir with only 2 plants. you want as much room as possible.
and it definitely depends on how big you want these to get. if you want to do really small plants, you could possibly do all 7.. but even there i would be afraid of the roots getting tangled together.
honestly i would recommend 2 or 3max.

5- yea def more lights. the more lights - the better + a LOT better yield. those expensive pro lights, like HPS systems or metal halide systems are really the best because you have to hang them up far away(i think a ft or 2) from your plants, but since they are so powerful they penetrate the plants from far away.. i dont remember the exact way it works, but with CFLs you need to have them really close - like 2-4 inches away from the plant. and what i do is just cover every part of the plant as best as i can with CFLs.

for the fan, really depends where you are growing. if the area gets hot, a fan might help but not too much. the fan is mainly there to get air flow going and to strengthen the stem. so just a normal little fan should be enough.. though im not sure. im using a little osculating fan at the lowest speed and its behind my lights, so not too much wind hitting the plants directly - but still getting some air flow going.

yup ph 5.5-6.5 - i would say 5.5-6.0 would be better
water temp - not more than lukewarm. "Lukewarm" generally means between 98 and 105 degrees Fahrenheit, 36.5 to 40.5 Celsius.
light - most basic/recommended is 18/6.

yea and good job, dont disturb them at their night time. get some pics soon and good luck!

My first grow too, so I'm no expert, but here's my thoughts based on my experience so far:

1 Should I be concerned about pH levels this early on? I haven't done any readings yet

Yes, the sooner the better. You got yourself a free aerogarden, so invest a little in a pH test kit or meter. If you get a meter you'll also need buffer fluids for calibration. You'll also need pH down and/or pH up (probably pH down). Get the smallest bottle possible, because a few drops have a big effect.

2 I'm currently running on 20h on 4h off, is this a good cycle for growth/ veg?

Probably a bit strong, I suggest 18/6, 17/7 or 16/8.

3 One of my plants is begining to show yellow on the ends of the leaves, thoughts?

Probably due to pH being out of balance, suggest correct to 5.8.

4 I am currently growing in all 7 slots, but from what I'm reading I should max the box out at 4

Probably 2 or 3. Depends if you are growing from feminized seeds. If not, you might only get 2 or 3 female anyway.

5 What about raising the lights over time? should I invest in more lights? I have a laptop cooling dock currently as my fan, is this enough?

Whether the lights are high enough depends on the model, and also whether you are using dwarf auto-flowering seeds. If you are lucky enough to have found a 3-bulb deluxe and are using auto-flowering seeds, you may find that you can get by. Otherwise you may have to detach the hood, get an extension cable and hang it from the ceiling, and place additional bulbs to the side. I can't advise on the fan.

Good luck!