Choosing the right pump

[sixspeed]

Hey, i am setting up a sump for my 30 gallon tank. I dont have the tank drilled so i am going to use a overflow box. I either want to get a 300gph or a 600gph rated overflow box. The only problem is picking out the right pump to match the rated gph of the overflow, i want to do this cheap so if a pump for the 600gph is too expensive i want to go with the 300gph. There is only about 3.33 feet of head height, and maybe 1 foot in horizontal distance. What should the gph be for the pump i choose? (for either the 300 or the 600gph box)

Can anyone give me any help?
Thanks

[sixspeed]

no one?

[corbett_n]

I have a mag 5 on my return pump for my 300gph overflow. I found it used on a local reef forum for $30

[Will520]

I had a mag 3 (rated at 350gph) in my 29g and it had a head height about about 3.5ft. it wasn't anywhere near enough so I upgraded to a mag 7 (700gph) which would give me roughly 600gph at the height i needed it to reach. the price difference between the 2 was $11 if i recall correctly.