Would No Flow On LR Work Like A DSB?

[rastaangel]

Just kinda mulling around some ideas for natural denitirication and ofcourse have come across DSB systems. I know they work by having low oxygen for the bacteria to do there job and I was just wondering if I took a large area in my sump and filled it with very porous rock and made a baffle so it had minimal to no flow on it would it have the same end result of a DSB or would it just act as any other live rock in my system?