If you don't have space for the CPR hang-on refugiums we posted earlier today, we've also got smaller in-tank versions that are 15% off until 10/1/13.
Refugiums are a perfect place for microorganisms like copepods, amphipods and baby brittle stars to live and breed without predation. You can also use the them to grow macro-algae to absorb nutrients like nitrates and phosphates from your tank water.
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