I am getting ready to move somewhere where I plan on staying and am wanting to finally set up my 55 for fw. I am planning on havine a limited number of cichlids and am planning on doing the lava rock background from duboisi.com w/o the caves (just rock on plexi-glass). I am trying to figure out how I could hide my heater and filter. Is it possible to make a box for one corner and put this stuff BEHIND it? Would I get enough flow/heat exchange if I drilled small holes in the background between the rocks? I am thinking I would have to use a canister filter to pull this off. As you know, the 55 is limited depth wise so any help is appreciated.