Do fiddler crabs fight?

Help with Fiddler Crabs?

• 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! 2 of the Crabs are A Tanish/Light Brown color, and one is a dark Brown/Blackish color. I can't really see a diffrence in the claw size, last night they molted their claw shells, I can see them in the bottom of their tank, it's cool, but their claws got smaller, not bigger. Could this be them adapting to the change of water and temperature? Are there any other distinguishing features between male and female Fiddler Crabs, like color? I left them in the bag they came in, with the store water, and I put the bag and them into the tank, so that my water could change the temperature of their water so they didn't go into shock from a high temperature change. I used Tap water for their water, BUT I am using a special formula/chemical, that the pet store told me to use, I put a few drops in it and it's supposed to "get rid" of the chlorine in the water, and everything else harmful to the crabs. I have a small 1 gallon bowl for the time being, and I plan on moving them to a much larger tank today, I think it's 10 gallons, but I'm not sure. I'll also be adding land into it, and pileing up rocks on one side, [store bought or should I use rocks from outside?] so that it'll create a half-and-half area, Land, and water. Once of the little critters already figured out how to climb one of the plants I have in the tank, so it's succesfully, "found Land" in way. Is there anything else I can add to the tank that'll make the crabs feel more at home? My mom would like to know if there are any LIVING plants that I can put into the tank for them to eat, and climb in. I read on here that there needs to be some kind of salt in the water, like Kosher salt, I don't have any of that, and there isn't any in their current water, they don't look effected by it yet, but how long untill I'll absolutely need to put salt in their water to recreat their brackishwater enviroment? I have a lot of questions, and to save you the trouble, I'll just make a list for you, 1.Their claws got smaller, not bigger. Could this be them adapting to the change of water and temperature? 2.Is there anything else I can add to the tank that'll make the crabs feel more at home? 3.How long untill I'll absolutely need to put salt in their water to recreat their brackishwater enviroment? 4.Are there any other distinguishing features between male and female Fiddler Crabs, like color?

• Answer:

  http://exoticpets.about.com/cs/rarespecies/a/fiddlercrabs.htm i found this online for you seems to answer most of your questions... one thing it doesn't answer is you should never use things from outside in a aquarium, it messes up the ph.