Decorator crab question

[Blacksteel]

I had a decorator crab in my 20 gallon reef tank which has some hammercoral in it. I woke up one morning to see my crab ripping apart my hammercoral. I wanted to coral to recover so I put the crab in another tank. Then on liveaquaria.com I read that decorator crabs can actually help propagate corals throughout your tank. I was wondering if anyone has any experience with a decorator crab helping spread corals? Or if anyone thinks this would be true

 

[Fishguy2727]

I can see it working in a larger tank, where their impact on any particular coral would be minimal, but in such a relatively small tank I think they would be more harm than good. They are interesting little buggers though.

 

[Blacksteel]

I was also thinking that in my small 20 gallon he would do more harm than good. But they really are interesting how they place things on themselves! As much as I hated seeing him rip apart my hammercoral he did look pretty cool crawling around with neon green all over him lol