ok guys my LPS started carrying fiddler crabs for like 2 bucks a piece. Can somebody give me some info on these little guys? Tank size food tank setup?

Brackish water, needs some type of land mass preferrably made with sand. Will eat other fishies like guppies.

does it matter what size tank it is?

I wouldn't go any smaller than a 10g. That should allow you enough space to build a proper habitat.

so if i fill it with water like 30% and have a rock wall on one side that comes up out of the water it'll be set up properly?

As long as you have a "beach" like area in there somehow, it should work fine.

I know this is an old post but I always went 80 land 20 water. I used sand as substrate with a waterfall filter. I used shrimp pellets from my local Jacks here in Ohio

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