Propagation - fish & corals

I am building a frag tank out of 1/4" acrylic, the dimensions will be 14"x14"x6". The frag tank will sit on top of my sump and the light that is shining into the frag tank will shine through the tank into the refugium. My question is what size pump should I use for pumping water up from the sump? Also what is the ideal spot to put the output and over flow for maximum flow?

here is a picture of my plan