Maybe you could use live plants like a nice Fig tree or something? I`ve still got a Fig tree from a snake tank I was working on years ago, the tree got too big in the end but your tanks sound pretty big. The good thing about these types of trees is you can train them to grow into certain shapes. Short of that, could you use some PVC tubing or similar? Disguised with fake greenery.....
Ryan...

(There aren`t many Ryan`s here in the UK, I`m not used to meeting other me`s lol )