Thanks, EmpPleco, but it seems that you need to become a member . . . I already have too many accounts on different sites, and anyways, this will probably be the only time I'll ever even be using it! Any other suggestions?
Thanks, Butterfly! Emma, actually, I'm not sure if it is a Betta Kit or not. It came from my friend, who used to have newts. Yes, they are Fiddler Crabs. ATM, they will not have to be upgraded. 5 gallons is enough for 2 Fiddler CRabs, because at full growth, they will only grow about two inches around. (So basically about 1 inch long)
By the way, I already know that my 2 Silver Dollars are WAY too big for my tank. When they become huge, I will have to sell them to my friend, who has a 60 gallon.
Well, actually, it's pretty easy. All I actually had to pay for was the gravel, food, and the crabs themself. I gathered together some rocks and shells I found on the beach, and I got my tank off a friend, like I said. I feed them HBH Crab and Lobster Bites. When it comes to maintenance, all that is required is that you clean their tank every week - a week and a half. This hobby of keeping Fiddler Crabs is easier than I expected it would!