DO IT!!!!
I got a new 90 gallon aquarium for Christmas (actually I bought it for myself as a present 
). I used 1/2 inch styrofoam instead of the thicker stuff, so I just had to be a bit more careful when transporting it, but the grout really dries solid. It works great and cost be less than $30 worth of stuff (at Menards, the midwest's local version of Home depot and Lowes).
I made the left side for the bearded dragon and the right side for two day geckos. I used live plants in the day gecko side, and the divider I made is also out of the fake rock. It was a little tricky to get to fit well enough, but it looks great. The cage and top was $125, but all decorations (including the rock, plants, substrate, stick on leaves) cost around $50. Whole setup runs about $250 (If you have to buy the heat lamps and fixtures, UVB bulbs, ect).
It also took a course of 4 days (no more than an hour at a time) to paint each coat and let them dry.
Here's some pictures:
And here's one of the rock before any decoration:
I have more pictures that I took while going through the whole process, but this was just the final product. Also, here's a little picture of the day gecko enjoying his new home:
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Brian Skibinski
Brian@MilwaukeeReptiles.com
www.MilwaukeeReptiles.com
Leopard Gecko Care Sheet
