Eels versus hitchhiker crabs?

[Delphinus]

Yeah I'd have to do something about that since this is an open top tank (no fish).

I'm just thinking about ideas on how to deal with an out of control crab population. It sucks having a tank I can't put corals in. I was thinking maybe triggers, but someone told me the same thing as you, i.e., although they eat crabs, they'd be surprised if they were the magic bullet I'm looking for.

Because it's a ritteri species tank and the ritteri is VERY large, I can't house it in another tank while I tear down the rock and treat each rock with soda water or whatever .. so I'm looking for alternate ideas.