So first off, let me apologize for the massive upload
I've been meaning to do this for some time now. Finally got it done and now need to catch my thread up to reality. At that point, of course, the updates will slow to a more normal level
...and on to the build!
2 grow tubs. Note the bulkhead connector. This will connect to a hose which will be routed through the wire shelf and across to the nutrient return reservoir. The height of the bulkhead connector on the tub is important for reasons we'll cover later.
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The other grow tubs (total of 3 - middle one pictured twice) with bulkhead connectors in place on the 2nd (middle) of 3 shelves. Yes, I know this is a strange setup; bear with me and the method to my madness will become clear
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Hoses attached and plumbed into the return reservoir. It's starting to come together!
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Here we have the whole rig with the nutrient return plumbing in place. Note the hose behind and above the middle grow tub: this is the nutrient delivery line from the pump in the primary reservoir. Connections are all in the back and difficult to image, but there will be some shots.
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View from under the grow tubs looking up at the return line routing. It'll be cleaned up and secured a bit better, but this is the general idea.
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...and here is a shot from the back. In the foreground top, the nutrient delivery line emerges from the primary reservoir. Below that are the 2 reservoir balancing lines which let the levels remain equal across the 2 reservoirs. In the background, we can see the return lines entering the return reservoir, with the 2 equalization lines going in below that.
Why not 1 big reservoir? There are reasons, but let's get the thing together before hitting the functionality issues.
[img]https://img828.imageshack.us/img828/3131/gen022.jpg[/img]
Same shot from the other side.
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Shot of the rig being filled with (for now) straight water. Surprisingly, I have had excellent results using my standard tap water. Please note that I understand this is unusual - most growers prefer Reverse Osmosis water for excellent reasons. I have been fortunate enough not to need it.
Note the nutrient delivery line now tied down on the top of the center grow tub and attached to a very simple DIY distribution manifold. More on this later.
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Close-up of nutrient return lines doing their thing. Whee!
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Interior of the primary reservoir. The white object on the right is a filter bag which contains my pump. Note the ugly hole for the pump's electrical cord. This will be cleaned up and sealed shortly
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A closer shot of the grow tubs with the nutrient delivery line and manifold. This is stupid-simple: the delivery line runs across the middle grow tub, terminating in a 'Tee' fitting that routes nutrient solution to each of the side tubs.
For the actual delivery, I simply drilled holes in the supply line and installed drip irrigation taps and lines. The lines got poked through holes in the lids of the tubs to hang beneath. They'll eventually be routed to spray on the underside of my mesh pots to directly feed the roots from beneath
[img]https://img641.imageshack.us/img641/3238/gen027.jpg[/img]
That's it for now, and we're nearly up to date. I have a few more pics to be pulled from the camera, will get to that at some point. A bit tired now for some reason
Thank you for reviewing my build/grow log to date! I hope you're finding this informative and enjoyable. Please feel free to ask any questions or make any observations you like. I will do my best to keep current with answers.
If it hasn't already been made blindingly obvious, I am NOT a professional at this. I started reading a few years ago and built my first rig 3 seasons ago. Since then, I've been perfecting my design and learning quite a bit. I'll outline my reasons and thinking as time goes on. For now, I'm just focusing on getting the thing up and running.
We (my Wife and I) were hoping to have the thing fully built and plants in this weekend. Unfortunately, we've been derailed by the weather, which has turned unseasonably cold and very wet for the past few days, so the build has gone more slowly than I'd like. On the happy side, our seedlings are all safe and happy inside...more current pics of them to come.
Thanks, all! More to come.
Please bear with me while I get my bearings 
It's not what the forum is about. Just presenting facts and my personal interpretation of where they are likely to lead. If you disagree, great! Let's take it to another thread, though, K? 
- Seriously, NOT LAUGHING AT YOU! It's just that you may as well have been in my head for the above chain of logic. You are totally right, BUT - what we have to keep in mind is that this system literally started 3 seasons ago as some 5-gal buckets and assorted stuff...back then, it made good sense to save $$ by not buying instruments. I was also seriously interested to see whether I could do hydroponic cultivation 'by the seat of my pants' or not.