Rat,
Are you stalking me?? lol
Are you thinking about making a 3D background for the inside of your tank? Will consider that is going to cut your tank down about 1/3. A 55 is already marginal, a 3-D background and you are going to end up with 20 gals of water! Which isn't going to cut if for the species you have chosen.
No one has done in photography in the Lake Victoria in years so I don't know if anyone knows exactly how it should be. You might want to check out the HIll Country Cichlid Club, there are several keepers of Victorians over there, and they may be able to shed some light on how they would do a biotope tank.
http://www.hillcountrycichlidclub.com/Cichlid Power!
Pam