I agree that they are majorly overpriced. It is definitely worth it - my old 75g wasn't reef ready, so I couldn't put one under the tank. Having a small fuge packed with macroalgae that I harvested seemed to help out in algae control a lot, as well as producing tons of pods.
Being turned off by the super high price of HOBs, I made one in the corner of my tank that worked really well. I took a small acrylic box (one of those ones used to scoop fish out of a tank, about 1/2 gal), drilled a few small holes in it for flow, and used a cleaning magnet to stick in on in the corner of my tank, with the open top about 1/4" below the water surface. I then put a mini pump in there to prevent the water from being too stagnant. Fill with rubble and macroalgae, and it was perfect and cost <$30! It was close to the lights, too, so no need to add additional lighting.
What size tank is this for.? And which model CPR are you looking at.?
While I'm not currently using a fuge ,I have before and they worked good. And the science supports the benefit of having one. The science also says bigger is better here. So look at the largest one you can.
As someone who dabbles with acrylic. I can say ,save yourself some grief and get the ready-to-go ,like CPR or whoever. Very likely cheaper than you think over the DIY and will look nice.
[I just like to tinker in the garage ,so I take the hard road.:hmm5:]
Looking at CPR AquaFuge2 Dimensions: 13" L x 4.5" W x 12" T for my 56g column tank.
I have the 56 column also and have the "regular" Aquafuge, without the skimmer. I have a rock, chaeto, and some other random macro algae that grows like crazy. Was it overpriced? I guess, but I have a great pod & mysid populations and my nitrates have been kept in check even with a well stocked tank and over feeding because I'm supplementing a mandarin. Even after five months, the mandarin is till hunting and pecking at the rocks in the DT so I'm pretty sure the fuge is providing pods to the DT for him.Looking at CPR AquaFuge2 Dimensions: 13" L x 4.5" W x 12" T for my 56g column tank.
I bought this very same one for my 90gal. about a month ago from BRS. Are they over priced yes, as is everything in this hobby. It is very high quality and I wished I'd have bought it months earlier it does an excellent job. If you decide to go this way spend the extra $$$ and get the light.