fiddler crabs

What are they called? Can these live in 10 gallon? How many?

Hey guys! New to the board, I am hoping to learn a lot from you guys!! I have 2 5g Betta tanks currently, and I have an empty 20g I am considering putting Fiddler crabs in... I am having a hard time finding information on their care, diet and so on. I look forward to learning everything I...

We rescued 2 fiddler crabs from Wal-mart and it has changed our fish keeping lives.  My kids are doing research and learning all they can.  We upgraded and expanded our tank and now have a second tank.  We have had successful moltings and seemingly happy crabs.  We now rescued a female fiddler...

I have a 5 gallon tank that currently has 2 crabs in it with no fish. I've read some things that say 1 crab is plenty for a 5 gallon tank and others that say it easily fits 6. I think 6 is way too many for a tank that size. I want to add 1 or 2 more but do you think that'll be too many for the...