I am doing an invert tank and would like to keep a variety of echinoderms, but I also would love to keep an arrow crab with them, I've seen videos of arrow crabs perched above sea cucumbers with no sign of predation (attached below). I have owned an arrow crab in the past and know they can eat snails and such, but knowing sea cucumbers are toxic maybe they know to leave them alone? I would like a second opinion.
![2024-05-23.png 2024-05-23.png](https://www.reef2reef.com/data/attachments/3594/3594363-540ead9c45195907580d7a7a41db6c90.jpg)
![2024-05-23.png 2024-05-23.png](https://www.reef2reef.com/data/attachments/3594/3594363-540ead9c45195907580d7a7a41db6c90.jpg)