In my opinion, refugiums are not nearly so complicated that you would need plans for them (like a protein skimmer, or calcium reactor)
I think that a refugium is simply another element of your tank (a second tank), it should have;
- lighting (almost as powerful as the main tank, but on REVERSE DAYLIGHT CYCLE)
- no predators for small organisms (these organisms will appear from the main tank in visible quanities since there are NO PREDATORS!)
- flow through with the main tank
The only thing that may inspire "design" is not getting your algae stuck in the pumps which are pushing water around!!
My refugium is a 4 gallon rubbermaid dishpan. I cut a hole near the top and put a bulkhead in, let it drain into the sump. Add a small pump from the sump that feeds to the refugium. Add sand, algae, det. kit, light, etc.
I currently have a pretty standard wet/dry filter/sump. It is about 20 gallons with the wet/dry on the left with no bioballs and a place for the skimmer on the right. I need to do something to allow for the amount of water from the overflow thru the fuge and need room for my skimmer. I fiured this would take some baffles etc. Thats why I am looking for a plan so I don't reinvent the wheel.
