Depends on what the overflow is rated at. You should base your return pump on the overflow rating not the flow you want to have in the tank. I am sure that pump will work but for a reef, you will want more water movement than that. PH's or a closed loop can take care of that though.
If you have 2 internal overflows, you should be able to handle 1200 gph
through them. A typical AGA overflow will handle 600+. Not sure what you have though.
*180 gal Display, 100 gal basement sump, 33 gal refugium, 3x250 MH, 2x160 VHO actinics, zoos, some softies, LPS & lots of acros and other SPS.
*100 gal prop tank plumbed into main system w/ 2x96 PC lights and 1x150 MH,