its not just boats. the original bio problem was discovered and written up in an app note from alco diesel, the diesel electric train locomotive guys. while i was an indentured servant in the '70s, (dam, i'm gettin' old...) we used some stuff called biobor to kill the little vermin that live in the oil/water interface.

i would assume theres something equiv for our tanks - anybody use anthing special?
anybody ever try to drain the bottom sludge out?

wmm