Another crab question!

[VFX]

I just brought home a large monti-cap frag & when I pick up the bag to undo the elastic band I notice 2 small crabs scurry into & under the cap.

The cap is mounted on LR rubble & I've tried shaking the damn things out to no avail.

I wouldn't mind them normally but the tank the monti is going into has some small sexy shrimp & small nassarius snails which I'd like to stay alive.

Any ideas of how to get the crabs out without damaging my monti?

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