New to Sumps.. can anyone help

Just got a 15 gallon used sump and need some equipment advice.
I need a pump and was told not to go under 400gph.. is this right?
Do you have any suggestions on what type of pump I should use?
Also, I need an overflow box. Does anyone have any reccomendations?
I have a 55 gal tank.
Any suggestions on how to set up the sump or what else to put in it will be GREATLY appreciated. I'm completely new to this sump stuff (and the reading material online seems complicated)
Thanks

 

http://www.3reef.com/forums/reef-aquarium-articles-how-tos/all-about-sumps-filters-fuges-79852.html

 

Thanks

 

I have a 300gph+ overflow box and a 350gph return mag3 pump.. but I you can use a mag 5 if you want to since there is pressure loss from 5' height.

 

http://www.3reef.com/forums/new-hobby/ultimate-newbie-guide-86462.html

http://www.3reef.com/forums/new-hobby/how-setup-saltwater-aquarium-89044.html

http://www.3reef.com/forums/reef-aquarium-articles-how-tos/all-about-sumps-filters-fuges-79852.html

http://www.3reef.com/forums/protein-skimmers/all-about-skimmers-skimmers-skimmer-85389.html






For those of you joining us that are new to the hobby - the best piece of advice you'll get around here as a saltwater newbie is 3Reef's slogan
"Go slow, let it grow."
And for those experianced hobbyists joining us - it's still good advice
good luck and post pics soon