I have a 16 x 32 inground pool starting at 3.5 ft and ending at 8ft. I need to change my pump and filter which is currently a hayward 1HP Super Pump and Hayward 244T Sand. The problem I have now is that when I replaced the liner 3 additional return lines were installed giving the pool 5 returns and 1 skimmer, all 1 1/2 plumbing and all individuall run. With my current pump, I am getting very low flow if any flow to the far returns should I upgrade pump size to 1 1/2 HP?