Do fiddler crabs fight?

Can Hermit crabs live in a 20 gallon fish tank with half land and half water with fiddler crabs? I want to know if they will fight.On youtube it had a video of Hermit Crabs in a tank with fiddler crabs.

Sorry to flood the question board out with my questions today, but I guess we have some very active tanks today. So, I've had this male fiddler crab for about 4 months now. He started out in a 5 gallon in my sons room, but my son decided he wanted to...

Okay, so yesterday I went to walmart and I decided I wanted a fish, well, I got 3 Fiddler Crabs instead! Their REALLY interesting and fun to watch, but I think I might have gotten 2 males! Or maybe 2 females! But I'm not sure, so I need help with it...

Its a 55 gallon community tank contains the following.. mollies, guppies, platies, kuuhli loaches, dwarf frogs, cory cats, and a very small common pleco. i have a whole bunch that i bought cheap at walmart and i read the back said it helps the fishes...

Can i house fiddler crabs and red clawed crabs in the same habitat? it would be in a 20 gallon long. i know they say up to 4 crabs per 10 gallons so i was wondering if half could be fiddlers and half red claws? i already know how to set up a brackish...

i want to know if i can put fiddler crabs with my two hermit crabs.

I know that the fiddler crabs found in pet stores are semi-terrestrial meaning that they need some salt in their water but what other things need some salt and get along with fiddler crabs. also I don't want too spend too much money so try to keep it...