Freshwater fiddler crabs

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Freshwater fiddler crabs

Post by casssch » Sat Mar 17, 2018 10:19 pm

My daughter is wanting to add freshwater fiddler crabs to her crab collection (thanks Wal-Mart). Obviously they would be separate enclosures, but the internet is full of conflicting advice. Where's the right information located so I can see if this venture is even possible?

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Re: Freshwater fiddler crabs

Post by wodesorel » Sat Mar 17, 2018 11:27 pm

Check out my fid thread in Other Crabs. I had them for several years!

The big thing is that you need to think of them as fish. They spend 99% of the time in or partially in water. They need a cycled and filtered aquarium kept slightly brackish. If you've never had fish, this means that the filter has to build up a bacterial colony capable of breaking down the waste produced by the aquarium inhabitants.

Never mix males! Even in a 29 gallon they kept killing each other. Females however so much better in larger groups. You can tell gender if both claws are present, but you can also tell if you can see their stomachs. While they look tailless, the tail is actually folded up and looks like part of the stomach, a wide one is female and a skinny one is male. You could easily do 5 or so in a filled 10 gallon.

Do not do a sloping ramp of sand or gravel, it grows bacterial blooms same as a flooded crab tank. Go with a floating turtle dock or structures that rise above the water line, and lots of fake planta so they can float at the surface.

Walmart crabs are treated like crap and the death rate is sky high. They keep them in freshwater in cups that are never cleaned and the employees often overfeed into bacterial and fungal infections. If they survive the first few weeks they do seem to live a full life of around 4 years.

Two tips I learned - the brown species they carry had better survival rates without a heater in winter. The pink species died on me with no explaination!

Oh!! And they are insane escape artists. I never figured out how mine kept getting out because I had the whole thing taped tight. They look like huge black spiders running around! Unfortunely my cats usually found them before I did.
Want to see all my crazy pets? @waywardwaifs on Instagram

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