BROWN SPOTS??

hey everyone, kinda new, im going to explain the setup and then the problem.

Someone suggested that bubble bucket growing saves space by making the resevoir also the planter, so thats the type of hydro im doing. i have one 95watt vegetative flourescent light hanging 3-6 inches away from the plants, and the plants are temporarily at different levels till i find a strong female because three are actually using the bubble bucket method and they are in the lightproof resevoir, and i have one mutant, one baby, and one stronger one all growing in rockwool cubes set on the top of the bubble bucket (3 inches under the light) theres about 7-8 gallons in the resevoir with half strength nutes, but i added another gallon of just water yesterday. 5 of the plants are within 3 days of eachother in age at about a week old, and the 6th one is probably 3 days old. i am using a modified dresser with aluminum foil lined around the sides for reflectiveness (couldnt find mylar) i have a fan in the rear left corner on low blowing airflow around there, and i have the dresser drawer faces nailed together as the removable front door to conceal them. i have black plastic hung just behind the doors to help lightproof it, and my bubble bucket has one 10-30 gallon single outlet airpump that has been running since the oldest plants were 3 days old, and i got a new airpump today that is dual outlet and im using 3 14inch airstones (starting today) before that, it was just one on the smaller pump. i am giving them 24hours of light because ive read that it keeps them growing all day, and the reservoir is lightproofed to the best of my knowledge.with the false front on, the inside of the cabinet is about 5 feet tall, 15 inches deep, and about 3 feet wide. the resevoir is a little over a foot tall.

MY PROBLEM is that one of the plants that is about a week old, actually my first sprout, seems like it has a thin stem and for a couple days, i staked the plant with toothpicks and now its holding itself up. i just bought the new airpump today because it seemed like there wasnt enough oxygen being put out from the original smaller airpump and i thought i was kind of drowning the plants because of the lack of oxygen in the water. they look a little flimsy, but what concerns me most is that there are brown spots on almost all of them. i know thats not a good sign, and i want to know asap how to get them back up to 100 percent. because of the small enclosed area it gets a little hot in there and the thermometer reads 84 degrees with a 42 percent humidity rating. if its too hot, what could i throw into this dresser to make it ventilate better? my problem is that this is growing at my parents house and has to be very quiet and discrete so i cant have some loud fan sucking the air out of the back or something because that could be noticed. this is my first time and im learning as i go, money isnt really an issue, but i was trying to save by setting up this bubble bucket all home made. anyone please help and i greatly appreciate all comments and suggestions. ;)

Oh yeah, i just noticed that the only plants that have the brown spots are the 3 ones being used in the bubble bucket. a friend told me that it could be the ph level, and if so, whats a cheap reliable ph tester and if the ph is too low what do i add, and if its too high what do i add?

You want to get yourself some PH down and PH up
elements at a local hydro shop or online.
helps the hydro-grower keep his water
the same as if it where in soil.
I only grow soil so you might want to get a second
opinion on this. Good luck, and what a stealthy setup,
thumbs way way up bro.

thanks nov :D shit's costing me upwards of 500 now i went back to the hydro shop and i could only discuss it as tomatoes, mention weed, and you get kicked out. so, as clear as i could be, i explained it to them and they said that using the general hydroponics brand nutes is one that is really easy to get nute burn, so they had me buy better nutes and im supposed to flush this out and run only water in the bucket for an hour, then put nutes in it so i hope that was the right thing..i also bought a bathroom fan to suck air out so i have total circulation, but mind you they never saw the plants firsthand to see what it is on them. i would still like to hear feedback from at least a couple hydro growers to see if everything is being done right and to see if anyone else says that it really is nute burn.

That does make sense, being nutrient burn.
only after 3 weeks you started feeding, even
at half strentgh. It most likely was too much
food for them. I would go with the hydro-guys
idea and flush. The next couple sets of leaves
will show if that improves the matter or not.
now to puff on some homegrown G-13xHashplantxNorthern Lights #5, peace