Converting a Hagen Aquaclear 500 Power Filter into a Hang-on Refugium
(or How to Promote the Peace in a Fish Household)
By Steven Pro
Side view
If you are a fish-geek like me, you have likely accumulated a basement, attic, crawlspace, or garage full of used equipment. This same graveyard of aquatic supplies is sure to bring you scowls of disapproval from your family, spouse, or significant other. It will also fuel disagreements when you feel your current inhabitants could benefit from the newest piece of technology to hit the market. "What do you need that for? Why can’t you use something from that pile cluttering up the garage instead? If you are not going to ever use any of that stuff, what are we storing it for?" To save yourself that kind of grief, put as much of it to good use as possible or get rid of it.
It was with this mentality that started me clearing out the garage. I was selling most of my "prized" stuff for ten cents on the dollar just to get rid of it. School had just begun. Winter would arrive in Pittsburgh before I knew it and if my wife could not park her car in the garage because of my fish stuff, I would have a long, cold season in store for me.
During this cleaning, I stumbled across an old Hagen Aquaclear 500 and a brand new Coralife Mini-Might. I had gotten the power filter years ago as part of a complete freshwater tank setup. I bought the whole thing at a garage sale, but I just wanted the tank and stand at the time. It has since sat in the garage collecting dust. The light fixture I bought new during a clearance sale at a local fish store. I had no reason to buy it other than it was only twenty bucks. A brand new, nine watt, power compact light fixture with the lamp included, how could I pass that up? So, that too went into the garage.
Recently, I decided to combine these components into a hang-on refugium. If you don’t know what a refugium is, briefly it is a place of refuge from predation by fishes. They usually hold some sort of macroalgae for nutrient export, hopefully a myriad of small creatures for plankton production, and perhaps a deep sand bed for denitrification. There is in-depth coverage of design options and inhabitants in Anthony Calfo and Robert Fenner’s Volume One of the Natural Marine Aquarium Series "Reef Invertebrates" if you are interested. A detailed discussion of refugia is simply beyond the scope of this article and likely unnecessary for the majority of the readers.
Converting this power filter was rather simple. The only tools you need are a Dremel and Superglue. What kind of reefer doesn’t have these lying around? First, remove the filter basket. Then, cut the lid so that your light has unobstructed penetration into the old media area. In this instance, I cut a 4" by 9" rectangle out of the filter cover so that this hole was centered over the now new refugium space. Next, take some of the lid material to create a barrier to keep the substrate away from the pump assembly. I started with a 4" by 4" square, but you will notice that the Aquaclear filter has a slight taper to it. This can easily be trimmed to fit snuggly and secured into place with the Superglue. It took me some time shaving the square to fit right, but once you have done that, you can quit. I ended up going a little further with mine. I took some more of the leftover lid material and made little tabs to help keep the light fixture in place. Again, I simply fastened these into position with the Superglue.