Extra small valve at bottom of buckets

[fnord88]

Hi guys, first time poster long time reader and ebb and flower. First thanks for all the info in the UC forum, its is awesome.

I am shifting to UC, which i have no experience with, however after reading nearly every post here ( it takes a while ), believe I can avoid all the common mistakes. I am very lucky in that a trusted friend organised for me to purchase a home made system from somebody he knew. His friend is a perfectionist, so the system is as follows:

6 * 20 gallon eskies ( cold box ). Joined by 80mm PVC. PVC runs through 8" ducting, which is then filled with expanadable foam for insulation.

6 * 600w chrome dome lights in cool tubes ducted outside.
1 * 600w HPS
( the eskies are aranged in a circle, 1 chrome dome above every plant, HPS in the middle. Note all the ducting for lights and 2 exhaust fans are all insulated for noise and heat as well)

The problem: My friend is OS, and setting up the system i have encountered a few puzzles.
1) As well as the 80mm PVC, each eskie has a small 20mm hole in bottom with valve attached on out side ( see pic ). Have come up with several ways they could work; suck water from each hole to increase negative pressure? Or push cold water from chiller to each bucket individually?

2) The control bucket has a 900l/hr pump permanently inside it. The hose attached matches the hose size (20mm), of the valves in bottom of eskie. I have assumed it is for the cooler? Included also is a 1000-2000 l/hr inline pump and a 2000 gallon/hr pump, which has to be submerged, can the return line pump sit inyour control eskie?. Not sure why I need all 3?

Photos of small valve are on their side sorry, tilt head 90 degrees and they make more sense.....sorry.

 

[fnord88]

No body has any idea? After researching the chiller i need, i believe he must have been using the 2000g/hr pump to run to the chiller. Except this pump is not inline it must be submerged. The 900l/hr pump in the epicenter i have no idea. The other 2000l/hr pump I was thinking may go in a return resovior? I have included PIC of another res that came with setup, only it is too small to be main res. It has only one attachment, which is a two way nozzel. So i was thinking maybe the lines at the bottom of the tank provide extra negative pressure, and suck it from both sides into the return resovior. The 2000g/hr pump is then submerged into this return resovior, and pumps directly to the chiller, which return the water to the epicentre. The problem with this type of set up is the input of water into return resovior may not match the output? In Pic i have placed two pumps, the 3rd pump cannot be removed from epicenter. The inlet size on this extra res is two the same size as the pipe running out the bottom of buckets.