[BrentD]

I posted a thread before about the 50+ gallon Hexagonal tank I have sitting empty in my kitchen. I still haven't done anything with it, but I'm thinking I'd like to do some sort of multi-tiered setup. I'm just not sure how to accomplish that.

How would I go about making ledges that would stay in place, not alter the water chemistry?

The tank is roughly 36" tall.

Here's the pic of the tank for reference:

 

[eser21]

have a look at vivarium builds as they normally build animal safe backgrounds.
Ill warn you though if you look too much you might end up having a vivarium!!
http://www.ukaps.org/forum/viewtopic.php?f=56&t=11063

 

[2in10]

Light diffuser structure covered with plexi, then attaching rock to the vertical parts of the structure so you can have substrate on the levels.

 

[vespers_]

two words: vertical paludarium

 

[Hoppy]

You could plant a single sword plant in the middle, and hang a pendant light above it, open top. That should look interesting.