Dwarf Zebra Hermit crab fighting.

[Scud]

I recently picked up a zebra hermit- a adult sized. A beautiful specimen, and has an adequate sized shell.
today I picked up another dwarf zebra. Smaller than the current one I own. Put them in together. The larger one won’t leave the smaller one alone. He flips him over and just prods and pokes into his shell. Is there any way to stop this aggression?
I have extra shells in the tank, and actually put the new crab into the fuge for his safety. But obviously I would like to put him in the display with the other one.
Any advice would be greatly appreciated!

 

[Bret Brinkmann]

Sometimes you get a crab with a mean temperament. What size is the tank and how much algae is there for them to eat?

 

[Scud]

Tank is 40g breeder, getting quite a bit of algae, tank is about 4 months old. Have some bryopsis, green hair, and a little cyano on the sand in the back. I think he is just a bit of a bully. He seems to have let up over the last couple days. Not sure what the initial aggression was, but he mostly leaves the new one alone now.

Sometimes you get a crab with a mean temperament. What size is the tank and how much algae is there for them to eat?