Hello i am at the planning stages of adding a RDSB to my system with around 18-20 inches of sand in a 30-50g drum or bin or some sort. Just want to know if they are effective on reducing nitrates? i also haven't figured out how to plumb it in along with a frag tank. I could use one of the drains from my main display straight into the rdsb but don't want any detritus getting in there. So i was thinking using a mag 9 pump ai nthe last compartment of my sump to pump water into a the rdsb and den let it gravity drain into a frag tank then back into sump, would that creat alot of air bubbles in the frag tank? or i could do it the other way around but if i put fishes in the frag tank the detritus would be a problem? so what do you guys think about this idea of a rdsb and how to plumb it in along with the frag tank? And could i add snails, starfish or some critters to stir the sand in the rdsb? thanks