If that's the case why do you use 1/2inch barbs?, why not 3/8?.
Like I said
I'd rather have the most water at the most speed. to me, with what I have, it seems having no restrictions and letting the pump flow freely are the way to go, unless you'd call a 1250 a high pressure pump

...
And why have a
restrictive outlet? what can that serve?.
I still think that block design is'nt the way forward. I think tuning the system to what you have is the all important thing.
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