Hi,
I wouldn't recommend that model for external, they tend to leak. Not real strong on pressure either, great for circulation at cheap price, but put a little head pressure like pumping 3 feet up and they slow way down.
If you are running external, i would recommend a true metal external pump. The GENX/Mak4 will get you over 800 at 3 feet, on sale for 119.95. The GENX PC30 will probably get you close to that flow rating and is only 99.95. They both have 3/4 in and out.
thanks