Hi all, In my search for the ultimate hydro system, I finally decided on a 4 site undercurrent DWC, to fit in the lower portion of my DR90 Twin tent. The reason I consider this the ultimate system, for me, is because I'm lazy and impatient. I wanted max growth rate, because I'm impatient. DWC bubble buckets would work fine, but didn't want the hassle of checking nutes and PH in 4-5 different bubble buckets. I would rather have them all share the same water so I can dose and monitor it all in one place. Finally, I wanted a controller bucket, so I can route a chiller, probes for the Bluelab unit, and a place to add/mix nutes before they hit the roots of my plants. The cost of purchasing a similar system ( http://cch2o.com/index.php?main_page=index&cPath=31 ) seemed outrageous to me ($800), so I built my own! I tried to use as many of the same components as the original, where possible. My parts (and retail cost) -Pump is a 250 gph Danner ($60) -Air pump is an Alita -15 ($125) -Unseals (about $45, but I bought extras) -5x 3.5 gallon rectangle buckets with hinged lids (about $50, shipped plus a couple spares) -float valve ($15) -Water chiller, Current USA ($100, used from a reef shop) -Air stones - Sweetwater (awesome!) 8x 3"x1.5", and 1x 9"x1.5" - (about $50 shipped) -Misc air tube, and 2" PVC, cement, hardware (about $50) -Bluelab ph/temp/ppm meter $300. Ultimately, I spent about $400 on parts, to build my hydro system. $300 on a Really nice meter, and $100 on a used chiller. That's puts my investment cost at the same as buying just the hydro unit from Current Culture, but I also got a killer meter, and a chiller included for the price of just a pre-manufactured unit. Aside from being half the cost, I have the same water pump and air pump as the commercial brand. But I have premium Sweetwater airstones. I stuck to a nearly identical design as the commercial unit. However one thing I did differently is add the PVD tee in between the two far buckets, rather than behind them. This allowed me to fit the entire unit in my 36"x36" tent. It would have been nice to have a bit of extra space between that tee, and the controller bucket, but I made it all fit. In hindsight, what I'd do different is paint the buckets until they're opaque, because what I did was use reflective tape on the kids, but a bit of algae is growing on the inside walls at the water line of the buckets (where I didn't tape) Luckily, the combination of chiller, and excellent aeration prevents it from growing under the water line. Additionally, I'd re-route my airlines into the buckets, as their location makes me have to bend the tub around the net pots. Not shown in the photos, is my chiller, and a tall vertical 36" fan. Construction was straight forward, I used a hole saw to cut my holes in the buckets, and connected them with 2" PVC and unseals (pain in the ASS to work with, but they are solid, no leaks!). I think the system's pretty straight forward. If anyone has questions, I'd be glad to answer! Any suggestions on improvements would be greatly appreciated. Note, I have a PVC union connection from the pump to the controller bucket, and a ball valve so I can route a hose to the drain. In hindsight, I'd have just glued in a T, or a Y and a couple valves to permanently mount a drain hose. But the union works fine, aside from a bit of splashing when switching to the hose. PS: It works like an effing champ! Absolutely amazing! My lights are Blackstar LED 240w each. My cat was a huge help in assembling the system, eating the fan leaves I trim from my plants, and playing with rogue hydroton balls.