DWC Overwatering Help (1 Quart Reservoir, 6" Micro-Bubble Airstone)

I am having a small problem. My friend told me to not worry about it since he grows hydroponically and this is my first go with it. The plant that is in the single bubble bucket is showing signs of overwatering. The airstone inside is a top quality micro-bubble airstone that was $10 for 6". Those are the only ones my friend uses and says they are the best. The plant also looked amazing for the first week and a half or so. This started a few days ago. I changed out the reservoirs and cleaned both containers today. Also cleaned the airstones, anybody got any recommendations for cleaning airstones? Currently the reservoir contains a nutrient mix, the reservoir holds roughly 1 Quart or 1/4 of a Gallon. The nutrient solution is also PH adjusted to between 5.5-6. The nutrient solutions contains per quart:

• .75 ML Boost
• .75 ML Grow
• .5 ML B1-Red
• [FONT=&quot].5 ML MagiCal[/FONT]

The plants in the 6 planter bucket look just fine and its basically the same setup just with 2 lower quality, micro-bubble airstones. The 6 banger also holds 2.5x more water than the single bucket hence 2 airstones. The weird thing is the plant looked amazing for like a week and half. Each week when I changed the reservoir and I would slowly bump up the nutrients and every time the plant just boomed with crazy rapid growth. It is showing no sign of a nutrient burn at all, just over-watering. When I fill the res to roughly the bottom of the 2" net pot, after the following 18 hour photo-period, the res will be down to about 1.5" to 2" from the bottom, so she drinks alot. About 75% of the time the reservoir is only about 1/3 full. So I dont think its a nutrient problem and I don't see how it could be slowly drowning the roots when it gets better than worse than better. . . and the airstone is more than efficient for that size container. the container is like 6.5" across so the airstone barely fits and its of excellent quality, I know someone who uses them religiously, and with how fast she drinks and how many roots are there, how could overwatering be a problem? Any help with be much appreciated.

Could it be that the black tape that is used to light seal the reservoir is soaking up light causing the nutrient solution to get to warm? That makes sense, The 6-Banger is covered with aluminum tape which reflects light and doesn't absorb it. Yet again it did just fine for a week and a half? What are the symptoms caused by having the nutrient solution to warm?

The first 4 pictures were taken today. The last 2 pictures were taken on Haloween, 2 days ago.

+REP to anyone who helps fix the problem.

Maybe it's me but I don't see any pictures...

Covering your container in black tape is certainly a bad thing to do, you want to relect all that light off, not absorb it. Having a reservoir that is too warm is a very bad thing.

There are no pictures and no descriptions of the issues so there's not much anyone can do for you.