it is difficult to get the flows to remain constant between the two outlets. skimmers like back pressure, while the return usually has none. so all the water wants to go to the return and not into the skimmer. the way around that is to put a
ball valve on the return to limit it. so now you are wasting a lot of total flow to run both outlets.
i am not saying it can not be done, but the pumps that work well for this are pressure pumps. they maintain a lot of their total flow with back pressure so you are not wasting much total flow by doing this. the problem with this is that these pumps are fairly expensive. usually near the $200 range. so you end up not saving any money. this is used for space saving reasons and not for economic reasons.
G~
