I had a set up like that fo awhile, using hoses instead of PVC. Here's one thing to watch. Always drain the hose outlets before filling. The water in the outlet end becomes stagnant and very nasty if not used for awhile. You don't want that water in your tank. I found this out when stopped using mine for awhile to use a gravel siphon to pick up mulm. When I switched back, the water stunk up the room (not the tank fortunately).
I would have the hose end upstream from the heater to "pre-heat" the water before entering the tank.