I have lake tanganyka cichlids in a 55 with two emperor 400 running. Home Depot play sand on the bottom and Texas Holey rock decor. My water is always crystal clear. I do 50% water change every month and clean out the filters. Besides topping off the tank every two weeks or so, it requires no maintanence. Well I add bacteria every week...but thats it. Don't know about the fluvials...but have heard that they work great. I just don't have the room underneith.

check out this forum...
http://www.african.uklinux.net/phpBB/index.php

and this one...
http://www.cichlidtrader.com/