Pipe organ coral question

[Redbird5]

I have a pipe organ coral that has been thriving for this year. Last week I got a pithos crab, on Sunday evening I saw the crab just before lights out near my poc and it looked like he was munching on hair algae in the pipe organ coral. This morning I fed my coral and noticed that my pipe organ coral might be a tad shorter than it was last night before bed. This was taken a few minutes ago.
If the pithos crab is eating it he's gone. However, in the week he's been here I've only seen him once.
If the evidence keeps pointing to him eating coral he's out of the aquarium. How do I catch him if I need to?

 

[Uncle99]

That crabs a herbivore so unlikely to eat your coral.
He may cause the polyps to retract when looking for dinner, but, it’s unlikely he will eat a healthy pipe organ unless he’s starving, then….maybe…

Leave him alone unless he’s a constant annoyance.

 

[Decamicron Labs Verified Sponsor]

Can't speak to what is causing your polyps to behave like that, or whether that particular species could be an issue, but if you wanted to catch something a cut up water bottle with some bait inside will probably catch your crab (and more).

Google "water bottle trap"

 

[Redbird5]

That crabs a herbivore so unlikely to eat your coral.
He may cause the polyps to retract when looking for dinner, but, it’s unlikely he will eat a healthy pipe organ unless he’s starving, then….maybe…

Leave him alone unless he’s a constant annoyance.

I had one pithos crab who ate my pulsing polyps then started on my hammer coral. They are opportunistic eaters. I fed him sea weed yesterday, but I never seen him so I can't know when to throw food in there for him and there's lot a of bubble algae for him to chow down on. The pipe organ maybe just waking up and I may be jumping to conclusions.