That may look kind of strange, if you devide it into 8 the sections would only be about 6' wide.
But I would imagine the best filtration would be to use seperate hang ons and treat each section as a seperate tank if you plan on using glass.
Personally, if I had a free source of 1/4 glass I would buil the entire tank custom. Do a long tank with seperate chanders. 48x10x10 and then devide it into 8, 6" chambers... each chanber would be about 2 1/2 gallons and you could filter each with one of these for a total of about $130.
http://www.petsmart.com/product/inde...ductId=3523858
Another option would be to use sponge filters driven by one large air pump.
You can get them cheap on ebay...
http://www.ebay.com/itm/New-2-Sponge...item19c923399f
Another option would be to build your own under gravel filter. That would be very cheap. Get a sheet of light difuser from Home Depot, $10 I think, cut it to fit the bottom of the tank, lay plastic window screen over it and glue down the edges with silicone, instal your devider walls, then run a strip of glass (about 2" wide down the coener of each devider. Cut the about an inch shrot from the top rim and silicone a strip of the left over light difuser across the top. Glue a piece of cross stiching plastic (Michaels, $.59 a square foot) behind the top pieces of light difuser. Then drop air lines with bubble stones in them.
Want to do it with less work involved? DIY under gravel powered by a single power head in the last chamber. Connect a piece of PVC to the powerhead output and run it across the entire tank with holse drilled in it for each chamber.
I hope all that makes sence. I can see it in my head, but describing it is kind of hard.