Crazy pH Fluctuations

Hello!

Figures my first post on this forum would be when I was having issues, but anyway...

This is my first grow/attempt ever. I plan to maintain a perpetual ScrOG, so that I can supply myself with meds from now on. I'm currently running one bubble bucket under a 250w MH and 4 weeks from germ, but I'm just recently starting to have issues.

Every time I check my res I find the pH is between 3.5 and 4.2! I tried to remedy it at first by dumping in a ton of pH UP mixed with distilled water till I got the pH to 5.6. Then, after realizing how dumb that was I mixed a new res worth of nutrient solution and swapped it for the toxic res. I made sure it was the same ppm as the original solution (~1100ppm w/ tap water) and pH'd to 5.8 when I swapped it, yet this morning I discovered my pH had gone back to ~3.8 overnight! I'm done messing with ph up/down tbh. I've maintained nothing but beautiful white roots and emerald green leaves (bar a few TINY spots) thus far by adjusting TDS of nutes appropriately, and my plant is still growing...albeit a bit slow for my liking.

My current nutrient lineup:
SensiGro A+B (Lucas formula with FloraNova Gro/Bloom next time -_-)
VooDoo Juice

I think the bennies in VooDoo juice are what's lowering my pH, so I'll mix myself a fresh res tomorrow without da' juice and post results.

I also have beneficial bacteria/fungi on standby if it's from an evil bacteria. Then I will build an army and crush it! (Atomic Nutrients Ben. Bac./Fungi)

Thanks in advance for your replies, all!

Images of my plant, and my whack pH
http://i.imgur.com/UgxOM.jpg
http://i.imgur.com/SecWW.jpg

Supz man. 1100ppmz total for Veg sounds high to me. I only rocked like 700ppmz through Veg and didnt get into the heavier nutez until AFTER the first couple of weeks of Flower. They look good tho. REally fluffy and lush shades of green. I just took the PH going down rather than up as a sign of too many nutez. Try watering them down a bit and go from there

I guess my nutrients were a tad strong...After doing add-back with nothing but distilled water yesterday/today my ppm has dropped to a nice 1000.

The pH was 6.0 after today's add-back, but a few drops of pH Down brought it to 5.7 . The bucket is taking care of itself again! xD

it is most likely root issues... voodoo juice uses anaerobic bacteria and is known to fuck shit up (in the Heisenberg tea thread). I would stay away from floranova in DWC, some people get root issues using it because it contains organics.