Some other versions of moving beds:

http://www.koiphen.com/forums/showthread.php?69028-Birdman-s-Fluid-Bed-Filter

One of my moving beds: (Scroll down)

http://aquaponicsnation.com/forums/topic/8826-filter-media/

I use a smaller media now that has more surface area per square foot than even Kaldnes and MB3 and is the cheapest on the market.

I get it from these guys:

http://alliedaqua.com/moving-bed-bio-media.html

BTW here's a really cool DIY S & G filter that is used as a secondary filter in some koi ponds to produce gin clear water. I like how he cleans the solids out too.

http://www.koiphen.com/forums/showthread...dman%27s+Filter

If pigs could fly bacon would be harder to come by and there would be a lot of damaged trees.