Just wanted to mention something regarding this build experience. If you hear noise in your custom loop build - it’s your pumps cavitating.
I was 100% wrong in assuming I had enough inlet pressure. Showed pic of system to a friend overseas and he insisted that my system was cavitating and that my loop was starved. We argued for an hour until I finally put more water in the loop “to prove him wrong”... he was 100% correct.
System went stone cold silent and water went clear.
To all those who mentioned that on this thread - you were right. I was wrong. Just fyi.
If you are building a custom hard-tube loop for first time - keep filling ‘er up until no more bubbles and nice and quiet.
Doh!!!!