HCA: Hermit Crab Association

I have a 20g long tank with a food, fresh and salt water bowls a coconut hut, a half log that reptiles would use, a cholla wood stick, and a shell yard. The half log is used big my bigger crab Reginald and the cholla stick lean up against the log and my to crabs like to climb up on to the top of the log. Then the coconut hut is used by the smaller one phosphorous. I wanted to know if there is some things that i can put in the tank that they can climb on and if anyone had any ideas of what else I should put in there because it is pretty bear. I will post a pic of the tank later.

If you want, you could add some fake or real plants for them to climb. In addition, you could also add some bridges, a second story (shell shops, moss pits) anything with plastic mesh, and even a hamster wheel. Believe it or not, many hermit crabs love to run around in/climb all over them