W/D Media Submersed

[garyl]

I know that when running a w/d system that the bio media is supposed to be above the water level so that the water trickles over it. I have always wondered what would happen if it was under water instead. Would it still work and maybe just not be as effective? After all there is bio in the substrate and rocks and they are underwater. Just curious. Can someone fill me in on this please.

 

[TankGirl]

It would work, much like biomedia in a canister filter works. All you need is adequate water flow, and the surface of the water exposed to the air provides O2 exchange.

 

[greenmaji]

the idea of it being above water is so that it has access to more O2.. if you supplement your O2 like under your submersed media with airstones you get pretty much the same effect.. otherwise it will just use the dissolved O2 thats in the water from surface aggitation as noted by TG..

 

[garyl]

Thanks to you both for the replies. I like the idea of the airstone. Never thought of that but I'm sure that would help with the additional air movement passing the media. Maybe a bubble wand would work. Interesting.