Just ordered

[Mugwump]

I don't run a closed loop on mine......works fine...and I can add to either end too...

I left mine up when I moved a yr and a half ago so it's just easy to use what's already there. It worked great for me. It circles my entire 12x12 fishroom.  I do like the setup you have though and if I move again I'll more than likely go that route since putting up the PVC was a pain in the rear

Heck yeah, why reinvent the wheel, if one's available......