I did not use any insulaton on it, the room will always be a hot room, wouldnt insulation also keep heat out? I was thinking it goes both ways, and this is a really hot room already, so i dont think it is a problem. I have a 2200W heating cable in the ground aswell, really delicious.
About the driftwood i also think id have to drive around and check the lakes around here..
I have had this idea of making small acrylic boxes, glue them on the sidewalls, in different hights, paint them black, and put some plants in there, since i have stingrays i dont think that is such a bad idea.. And I personaly think it would be ok with a few plants in there(colors). What do you guys think?