Ok so chiller outside the room. I was reading copper is not a good material for the exchanger so im looking for some titanium ones.
I was planning on using these totes(
http://www.homedepot.com/p/HDX-27-Gal-Storage-Tote-4-Pack-ST29201508/205763803) just because they're flat. So I will use a smaller tote for the control bucket.
Though I just did that math and those totes at 8cubic feet which means they can hold about 60gallons of water x 8 thats way too much water.
So would this layout work better?
View attachment 3454091
Also I hear something about a pump needed for the chiller. So the control bucket have two pumps? One to distribute the water to the buckets and one to pump water into the chiller?
First, unless your nutes are way off the scale wrong, you'll never have to worry about problems with copper in the water. What it will do is kill roots that come in contact with it, which won't happen if you put it in the control bucket where it belongs. Half inch x ten feet or so of soft copper HVAC tubing, it's been treating me just fine for years. Easy to work with, obviously excellent heat transfer properties.
It appears that you already have the small chiller in question? If so, then you may as well just run nute water thru it too, as it's too small to have a separate circuit.
Therefore, you can still use just one pump, just add a fitting like it's going to a tubsite, run your half inch line from that to the chiller and run the return straight back to the control bucket. If you want a little insurance, get an inline filter and install it just upstream of the chiller. Check it often.
In effect, this plumbs in the chiller just like a growing site as far as your water circulation is concerned and it will mix with and cool your system effectively.
By the way, the link to totes above goes to 27 gallon tubs, which by an amazing coincidence hold about 27 gallons of water each. Just wanted to mention that before it the your math off...
I'm gonna wanna taste some of what I'm helping you grow... everyone has their price!