If you look at the design carefully. Every time you use it, the water and dirt in sump trap will indiscriminate trapping good diesel.
I had a captain/owner once proudly announced to me how good the filter work by trapping so much bad diesel. I looked at the bottom of the filter, it was all clear diesel. He just tossed over board.
I almost die when I saw that. There are lots of morOOns in this world.