What your proposing is not a RWDC system. I think what you should think about doing is just use a control bucket that your rez fills and drains. Its an ebb and grow controller bucket.. but you just reverse the cycle so that it is mostly flooded and the buckets get drained the rez where you can adjust levels, get chilled, etc several times a day.
I am running a 8 bucket set up like that in one place and an 16 bucket setup like that in another. Each row of 4-8 buckets has its own line that feed the control bucket. 3/4 lines really help things flood and drain faster. You must have a massive rez dude!! what is it 200 gallons?
My only other suggestion.. and shame on you green thumb for posting THE WORST fucking airpump in the world!!!
Those things really truely suck balls. If your still using one than I would highly highly highly suggest that you check out the pondmaster pumps...
http://www.ebay.com/itm/PONDMASTER-AP-100-DEEP-WATER-AIR-PUMP-9150-CU-IN-MIN-/330665713828?pt=LH_DefaultDomain_0&hash=item4cfd3660a4
that thing will pump out 150liters/min and it is completely silent. seriously, I can't hear it with the oscillating fans running, it doesn't operate at 120 degrees like those compressors do, and it has a much better design with replacement parts when and if you need them. I just bought one a couple months ago and was blown away by the difference. I immediately bough another. I have three of those 110 LPM "commercial" pumps that i'll sell you for $20 plus shipping.
ok rant over, but seriously green thumb, you should check them out.