I'm confused!
I have changed my plumbing design too many times to count now.
Basics:
700 gallons - formal block pool
No-niche filter and bottom drain for pump intakes 2 1/2" pipe on both
Pump: 750 GPH

Original design would have pump drawing directly from these to lines,
but I've been looking at DIY vortex microstrainers
(http://livingjewels.com/DIY/vms/vms.htm) and have come up with a design
I think is terribly clever g. the pump would now be pulling from a
gravity feed, open tank instead of directly on the intake lines.

The questions a
-Can two 2.5" lines keep up with the 750 GPH pump (designed to be feed
by 1 3" line)??? Is there some rule of thumb for this?
-Will the no-niche skimmer still work properly just being gravity fed?

If no, then I wonder why I couldn't seal the settling tank and keep it
under pressure? It would definitely have to be more substantial
construction, but I can't see how it would effect how it works.

Mark B.