20 long nano reef display and im currently building the overflow to a 20h to serve as the refugium. The tank has been up for 5 months. Also if its does not need to be live sand what should be used?
For a deep sand bed or plenum the TYPE of sand will dictate the depth of the bed. Some oolites need only a few inches while bigger sand particle sized sands will need a much deeper sandbed. It does not need to be live sand. You can also use reef muds which do not need to be as deep.
CaribSea makes some nice sands. Here is their web page to show which sands are best for different methods.
http://www.caribsea.com/pages/products/d ... http://www.caribsea.com/pages/products/o ... Remember on DSB to not have much love rock or junk on top of them (more surface area=more efficient).
I have used this in my nano's DBS refugium with some plants. It is AWESOME (I have the setup in the diagram minus the bioballs - i use rock frag instead of bioballs because the bioballs are terrible compared to live rock):
pets question and answers,www.5d2d.com
http://premiumaquatics.com/aquatic-suppl ...
if your putting the DSB in a refugium then it should be 5-6 inches. 4 is minimum and you dont want more than 6. The sand does not need to be live, it will become live in time. I'd go with fine argonite. For a DSB you want a very small grain sand close to the grain size of mud if possible. Just note that a DSB needs to have a good current running over top of it and you should sift small areas of it periodically to keep it clean.
