Bilge cleaning

[pctarmor]

My theory is that the previous owner dumped a ton of oil/vdrive/trans fluid in the bilge at some point because I have triple checked and I'm not leaking a thing but every time I get water in the bilge and it pumps out I have a massive oil slick in the water. Not to mention my center bag is a damn mess from stuff sloshing from underneath the gas tank. I have used spray on bilge cleaner at the start of the season to get stuff underneath the engine relatively clean but I think there is still a bunch of junk under the gas tank. What have you guys used and done to get nasty stuff out from underneath the gas tank?

[CornRickey]

I'd put a couple scoops of Tide in it and let it slosh around for a day then drain in ot on land and rinse.

[villain]

Dawn dish soap. And oil absorb pads.

[angus2112]

i keep tide pods on the boat throw 1 in the bilge every month does not foam up and cleans well