Is this (short spine) urchin aggressive?

[hellokevin]

I've had this urchin for about a year. My tank is also about a year old. Recently it damaged and tried to eat part of my candy cane coral twice, and I used a container like this to separate him while the candy cane coral was healing. Thankfully that head has regrown its fleshy part.

I let the urchin out overnight, and this morning I saw it cracked open my tuxedo urchin.
Are short spine urchin usually aggressive like this? I'm thinking of getting rid of it, despite it being part of my tank since the beginning. I've been feed it shrimp pellets and algae wafers every day, so I don't think it's being aggressive due to being hungry?

 

[Tahoe61]

Aggressive not likely, potential coral eater a distinct possibility.

 

[Tobias517]

Looks like a tuxedo urchin. I have one it doesn't necessarily eat the coral but can tear meat corals & other fleshy corals up.

 

[Kasrift]

Looks like a tuxedo urchin. I have one it doesn't necessarily eat the coral but can tear meat corals & other fleshy corals up.

Purple short pincushion urchin. But should be essentially the same, herbivore.

I don't think it would eat a coral.

 

[hellokevin]

Sadly I sold it back to my LFS. He was one of my original inhabitants. My new system will have a sump where I could put him but it's not gonna be ready till June