Algae in res

I've ran waterfarms individually before and never had any issue with root rot, algae or any sort of slime. Now that i have 10 of them daisy chained together recirculating i have nasty amounts of slime in my control res and things are getting out of control.

My initial instinct is that i have a light leak somewhere so double checked all the covers on top of the buckets. No light leaks were found..

I have a waterchiller running keeping water temps @ 65 degrees. PH is at 5.7 and PPMS are at 400 at day 12. The algae hasn't seemed to find its way into any of the individual buckets which is real strange and it seems to be lurking in the control res only. I'm trying to nip this in the bud before it gets out of control so i hit it with a few ML's of Clear Res which is a chlorine shock product that should kill the bacteria.

My question is what on earth could be causing this and what should i be doing? The control bucket is the standard beige one from GH, is translucent, and is pretty close to the edge of one of my 1000 watters. I'm thinking light could be penetrating the plastic control bucket? Should i wrap that that in mylar or tinfoil or something?

Also, I got hasty when i was setting up and didn't properly soak a few new bags of hydroton i bought and I'm paying for it now. The PH swings are just unreal- i have been adding tons of PH down everyday to get it back down. Last night i PH'd it down to 5.6 and this morning it was back up at 7.2!! Too bad i already have my sprouts going otherwise i would just re-soak the stuff in ph'd water.

Any help is greatly appreciated! - Dub

I think you answered your own question already right after "what on earth..." and your instict is right. If translucent boxes were an option I would not have had such hard time finding one suitable for my system. It explains why it only occurs in that rez, so yeah, I'd cover it up asap.
Obviously clean thoroughly as well. Will make it easier on the chiller too.

If your res doesn't have any circulation that might be causing it too. I have a homemade 3 bucket recirculating/dwc, with Waterfarm drippers adding a top drip and have noticed slime on the walls of the res bucket but not the individual ones. The res bucket is the only one without an air stone or continuously moving water. The buckets I use are completely black with no possible light penetration.

Gotta agree, you answered your own question, your control bucket is too transparent, cover it or get a darker one.

hydrogen peroxide in small doses will kill the algae

Cool, thanks for the tips guys. I'm gonna cover it up and hopefully that does the trick. I'm a noob at hydro so i keep second guessing everything making it more complicated then it needs to be. I'll take some pictures and get another thread going after i get the room cleaned up.