What kinda crab is this?

I'm a total newb. He's probably as common as they come.

Alls I know is... he sure eats some SERIOUS amounts of algae, and boy oh boy, does it come out the other end as fast as it goes in his mouth!

yeah, the picture quality is awful... an no, I'm not asking about the hermit who showed up for the shot too.

 

Yeah, looks like a common mithrix crab to me. I've seen them green or red like yours. They are great at eating bubble algea.

 

Thanks, I googled it. It looks about right.

I ask because I'm a little concerned about his food supply. He seems to be doing great, and eating constantly, but I'm not sure what else to feed him than algae? I'm guessing the frozen food the clowns eat should be good every now and again right?

 

He will find any leftover food that your fish might miss. I have two myself and I don't feed them at all and they are still with me today.

 

maybe a red emaerald

 

The shape and look definetly ressembles an emerald crab, I've never had one that redish color, is it coralline growing on him maybe?