I have an under construction IG gunite 22 x 46 pool, 3.5 to 8 foot depth, ~42K gallons. I am planning (12) 1.5 inch wall returns, (4) 1.5 inch floor returns, 3 skimmers and 1 drain all at 2 inch. All pipe is to be run back to the pad into manifolds. All the runs are long (100 to 150 feet). The reason I have so many returns is to maintain circulation in odd places like the beach area, on benches, behind stools, etc. I figure I can always plug them if necessary but can never install them after gunite. I will probably use an Intelliflow pump. I may also loop two returns and use 2 inch pipe instead to reduce the number of runs. However, in either case I seem to have much greater pressure capacity than suction capacity. Am I headed toward a problem with cavitation or low return pressure?
I want to adhere to the big pipe/small pump theory. But I am not sure if 3 inch pipe for skimmers does any good if each end of the pipe is reduced to 2 inch. Any opinions are appeciated. Oh yes, I also have a WF, long run and 2 inch pipe but of course it will have its own pump.
Thanks for any advice.