Parts Of A Refugium

This can get really complicated really fast. I'm going to list out some of the features that you might consider in a refugium.

1. Macro Algae – Various types of non invasive algaes can be introduced and used as either food, habitat for feeder animals and/or chemical balancing.

2. Micro Algae – Usually in the form of some sort of Algae Turf Scrubber, the use of standard algae as a nutrient export.

3. Lights – If you have any sort of macro you will need lights. Luckily, macro has a lower light requirement than our main tanks. Algae's in general also prefer a redder light, lower on the Kelvin scale. For Macro's a 5100 or 6000k light is perfect. For microalgae (turf scrubber) 2700k is the most common. Generally macros need 2 watts per gallon in a standard refugium.

4. Deep Sand Bed – Deserves an article all to itself. Will go into detail in the individual build outs. A Deep Sand Bed is at least 3-4" of fine grade sand that creates a layers of increasingly lower oxygen levels as you go deeper into the bed. Water naturally flows (albeit slowly) through these layers using diffusion. The cool thing about them is that the bacteria in lower layers are able to process Nitrates into nitrogen gasses that escape harmlessly into the air. This effect also happens in the anaerobic layers of our live rock.

5. Live Rock – Not only provides the benefits of live rock in our main tank but adds some layers of biodiversity to the 'fuge. Also provides holdfast space for those macro's that need it.

6. Live Mud – An interesting type of substrate that gains popularity every few years is live mineral mud. Mud provides an anaerobic zone in only an inch or two of space while providing substrate for several types of macro and some true vascular plants that cannot take hold in sand or rock. I personally don't believe the hype around "miracle mud" but do think that mud as a substrate has a lot to offer.