I don't think 2 gfci in tandem is a good thing. I believe you will continue to trip the gfci. I am not an electrician, but I have heard about this on home improvement shows.
Made my chiller after reading this thread. I really liked the connections that AHB sells, but didn't like their price so I built my own. Cost me about 60.00, but I didn't shop around for deals at all, and took about 15min to put together. Thanks for the great ideas Bobby.