That was my original plan. I was planning out my course of action moving things over and was thinking about how to make the modifications to the 30 after I empty it and figured I could just use the 10 temporarily..... Then wondered about just keeping the 10.... So I think I'll just plan on using the 10 until I can make the modifications..... What size return pump would be optimal for a 55 with a 30 gallon sump?!?! I want as much flow as possible without stirring up my sand..... Any recommendations with this?