New Little red emerald crab


I know that I don't know
Hi everyone,
We were at the LFS yesterday to get RO/DI water and to add a few members to our CUC. My son as well as the rest of us love the little crabs. We picked up a little emerald crab that is red. Nathanael, my son likes the irony of a red emerald crab. He named it Holly and when we add a green one later it will be mistletoe. We love plays on words.
He has been very busy. Without his claws, he is only about as big as a penny.

How many of these little crabs can we have in a 40 gallon. We are adding a wet dry sump in the next few weeks.