Sump advice

[DannyBWell]

I'm currently designing my first sump it's going to be a wet dry trickle filter with and overflow box and I'm going to have 500 gph pump and I can't figure out what size pipe to use I think a 1/2 inch would be ok it is rated for 480 gph is that not enough should it be more than the pump since it only enters the overflow as fast as the pump can pump the water up from the sump?

 

[Andrew McFadden]

It shouldd be fine because the head height on the pump will slow it down.