Sorry I've been absent... great job Martin as always. It's been too hot for me to test, actually I've done one run the the GTZ but with these high ambients, I won't do it. People are now beginning to understand the consequences of pump heat, this 'OMGWTFBBQ I NEED TEH UBER FLOWZRATEZ' is laughable. Sure more flow is always better, the caveat is that it comes with the cost of increased heat, which, 9 times out of 10 will send your temps backwards. I still can't believe that no one has made a PD pump or a screw pump for our application, would own all centrifugal pumps like $2 ho's