Refugium question...

[StickyTuba]

Can anyone tell me what a refugium is for?

The only guess I can make is it is an added filtration system?
Thanks

 

[electrikat]

It is added natural filtration. It is also a refuge for certain critters that may be injured or being picked on. It is also a good place to grow pods and algaes for feeding your inhabitants. You can also use it to keep small frags of corals until they are firmly established on their rock of choice. It also adds water volume to your system and can be a great addition to any natural environment.