Time to buy a pump but I need some help

[MikeP]

I'm setting up a 190g reef. One of the last peices of equiptment I need is a pump. Here is the info I can tell you. I have one corner overflow and one return bulkhead. The overflow and return bulkheads measure 1.25 inches inside diameter (not sure if that rounds down to a 1 inch bulkhead?). I will need a submersible pump because my sump is an old 55g tank and cannot be drilled to hook up a external pump and besides I'm a little cramped for space. There will be about 5 or 6 feet of PVC between the pump outlet and the return bulkhead with two 90 degree elbows. How many GPH should I be looking for? I think when all this is factored in I want about 8 or 9 hundred but I'm not positive. As I understand it, there is a balance between overflow, sump, and return. If the pump is not powerful enough or to powerful I will run into big problems. If you can suggest brands/models that will also be helpful.

Thanks for any help