Help with putting sump together!

[MrGemini]

Good Morning all,

Quick Question. I'm going to be re doing my sum for my 125g dt, I'm either going to use a 20high or 20long due to space under the tank. both designs will have some sort of fuge but my dilemma is, should fuse be before or after skimmer? any help will be beneficial I will post sketch as soon as I complete the sketch up​

 

[joekool]

After skimmer. Skimmer where water comes in. Then deep sand bed with fuge above sand. Then return pump section.. Best out come for you.

Deep sand bed takes some time to get functioning but eats up nitrates well.