Well it's been about a year since I built my new cage for my adopted C. Similis that his previous owner had no idea what to do for it. He is about 3 or 4 years old, hard for me to tell.
Here is what he looked like when I first put him in his new cage after I had him for about 6 months nursing him back from the brink literally. The rock he is on is 35" long and about 10" wide. It is the same rock in both pictures and in the same place in the tank. The rock his tail is on is another 24" long.
This is a picture of him from tonight
And this is what I got for my troubles



