Anyone using eductor for your reef?

[regal]

Upgrading my plumbing for my 400G reef and need some advice . Current using sequence barracuda pump for return ~ 3000gph with 4X1-1/2in pipes for return. I'm going to install the 4-way OM and the eductors so that only 2 outlets will be on at a time. So what size eductor should I use? 3/4" or 1". The output end of the pump is 1-1/2" which splits into 4X1-1/2". Is 3/4" going to be too small?