I wouldn't split the return piping there personally. If you want dual returns but only 1 return pump, split it inside the tank in my opinion.
Mine goes up and over, then down to the sand bed and tees off. I actually have a tee about halfway down inside the tank for 3 total splits. I put rocks over each split and built cave structures for the nozzles to poke out of but not be overly noticeable.
Inside the tank will help you lose less flow as each fitting going up drops the pressure available at the tank which, in turn, drops the flow.





