i decided to make this instructable
Most of the problem is about how pet store employees are miseducating buyers and telling them the exact opposite of supplies...
Step 1: Supplies
-A 5 gallon tank (the bigger the better)
-a heater (Yes fiddlers get cold)
-A filter (Go for the internal ones for fiddlers because fiddlers are great climbers and can crawl up the intake tube and escape)Never go for undergravel filters for crabs...
-Sand (Fiddler crab legs are designed to crawl on sand,don't go for gravel because it makes it hard for them to crawl on and believe it or not fiddler crabs will die of frustration)
-Sea Salt (Fiddler crabs live in brackish water-half salt half fresh-and will die in months if in freshwater)
Note:Fiddler crabs are NOT semi-aquatic,remember they live in beaches not the ocean
Step 2: Determining the gender
see picture below