Takes a hell of a lot to make hemp rope rot. That's why ocean ships still use it to this day.

I have rope in a couple of my cages, no issues. But they dont have a lot of heavy contact with water, just with mist and they do dry out.

But anything left wet without being able to dry out - be it branches or rope or whatever- is probably not great for cham feet. Possible for fungus and bacteria to grow in any warm, moist environment.
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Sandra
BC Canada