Need a couple crab IDs

[Gomer]

I knew I had the brown one but didn't know about the light colored one. I THINK that one of them is the reason why a fish won't survive in my tank more than 3-4 days. I am re-doing my BC-14 and that is how I found the second one.

Any ID's on either of them? Any additional info?

They will be hermit food tonight if not deemed safe lol.

 

[LordHelmet]

the brown ones pinchers look like the pincher's from a emerald crab? algae eaters? but thats all i'm basing it on. probably not safe.

 

[Raddogz]

Brown one looks like Gorilla Crab - not reefsafe

not sure about the lighter colored one other than that is the coolest design on it's top shell

 

[tuberider]

The big dark one looks like a mithrax, it has flattened tips on the claws for scraping algae. The Other crab looks like trigger food.