refugium

[J19Reynolds]

What is the purpose of a refugium?

 

[willbratz]

http://www.ehow.com/about_6113978_purpose-refugium-reef-tank.html

 

[J19Reynolds]

So you don't HAVE to have one?

 

[Shirtlessbill]

What is the purpose of a refugium?

It's a place of "refuge" for the tank. Not only does it add water volume to your system (which in turn creates a more stable system) it also will act as a natural filtration if/when you put in the proper algae. I won't ever do a tank (fresh or marine) again without one.

Also it can be a pretty cool spectacle if done right.

 

[Keithhjs]

Most reefers keep some macroalgae in there which, helps remove nitrates and phosphates along with giving a safe "refuge" for copepods, Amphipods, etc to grow and keep the DT supplied with.