Commercially available refugiums

They come in a variety of shapes and styles but, all serve the same purpose. A place of refuge for delicate specimens or food stock like copepod's and amphipods. Refugiums are also one of the most efficient ways to benefit from the use of chaeto or other macro algae. In a refugium the macro algae will act as a polishing filter for phosphate and nitrate. By using a refugium you can have it on an opposite lighting cycle as your main reef tank. This will help stabilize the night time pH drop you would normally encounter without the use of a refugium.

Here is an example of a popular and somewhat expensive retail refugium.

DIY Refugiums

The same thing can be accomplished with a 20 gallon long tank, a few panes of glass and, some silicone. You will find the DIY refugium much cheaper and endlessly customizable.

A very cheap and scaled down 10 gallon version is a good start for a first time DIY project.

A 10 gallon in progress. Note the pane of glass being supported by a deck of playing cards and masking tape while the silicone cures.