Jeff, Thanks I'm looking into that right now. I know I should have ordered more of those. I just used my last one. I can't seem to find this application of the SUD115 anywhere. Makes total sense though. Would 2 of them back to back be safer?
Shopping list.
Stainless steel coil for the aquaponics heat exchanger
http://www.ebay.com/itm/304-304L-Sta...-/290552612112
45% Silver braze to braze the copper to the stainless
http://www.ebay.com/itm/98102-Lucas-...item2357e81a0a
SUD 115 Modified drier/ Oil Separator
http://www.ebay.com/itm/Copper-Liqui...item3f4eb94254
3 way valve
http://www.ebay.com/itm/RANCO-V3-310...item3378ddafdf
I'm getting the 300 feet of 3/8 copper locally because its much cheaper that way. And I know what I'm getting.