Special Refugium Sand ?!

Some refugium sands / muds claim to have elements and minerals that slowly get released over time making the the system more stable. I use reef grunge or live rock mud that you should be able to get from your local lfs. I let people come in every year to clean out my live rock vat and they keep all that they pull out. Nice thing is its full of benifical fauna and will populate a system fast with pods and such. I have used Livesand before and the special stuff but prefer the reef grunge.

Owl: there is Refugium Mud that typically goes under the sand...but that is for a very specific fuge. From what I have been told it needs to be replaced every few months as all the nutrients are drawn out over time (or just a great marketing ploy). As for special sand. If they mean there are different types that are good for a fuge, then that is possible. I like to use a layer of aragonite on the bottom - about 2 inches and then 2 inches or more of "sugar size" sand. From there it is all a matter of price and aesthetics.

You can pay for color, live vs not. Hope that helps. I have to say it isn't an area where I would spend a lot of money considering it has a purpose and it isn't supposed to look pretty. It should be filled with Macroalgae, copepods, amphipods and all manner of microfauna.