The Refugium Debate: Do They Actually Work? Part I

To Refugium or Not to Refugium debate has been going on in the saltwater community for as long as I can remember. For the first part of my saltwater keeping years, I was a Fish-Only with Live Rock (FOWLR) aquarist. Maybe it was because I mostly kept freshwater fish-only aquariums prior to saltwater keeping or maybe because reef capable lighting seemed too expensive back in the day and reef keeping knowledge was mostly in books that were not available in most public libraries or my college library. You’ll have to remember that Google pages for aquarists were not prevalent nor was a forum like Reef2Reef available back in the day. Reef2Reef started as Club-Zoa.com, BTW.

What prompted this retracing of my steps back into the Olden Days, as my sassy 4 year old tells me, was a recent Question of Day on Reef2Reef forum. The small poll showed that 53.8% of active Reef Keepers (reefers) currently have a refugium.

Do I have refugium? Yes, I have a refugium on my 360-gallon mixed-reef saltwater aquarium. However, I wasn’t a believer in refugiums for a long time.

I wasn’t a believer mostly because I thought you can keep nitrates and phosphates low mechanically or chemically without adding a refugium full of algae, of which you’re trying to keep out of the main display. And because I followed a person with a very large mixed reef system (800-gallon main display) who had a separate very large “natural” refugium (think mostly live rock, some macroalgae, and average lighting) that all of the main display water would cycle through. For this particular person, this style of refugium did not work. He kept meticulous records of his parameters and his conclusion was that he would have to have a refugium exponentially larger than his current one in order to keep nitrates and phosphates in the low ranges that he wanted. So why didn’t a refugium work for this person? To Be Continued…