I want to keep a crab, 3 gal tank, room temp water, maybe no filter?

[CoralKitty]

I used to be into reef keeping, did so for 10 years, had clams and SPS and it was all going so wonderfully... until I blundered and did not quarantine some new coral pieces long enough, I introduced sea spiders to my system, lost nearly all my coral and lost heart in the hobby, been tankless for years now.

I don't want to get back into reefs but I have been thinking about a childhood pet of mine and I would like to have a crab. As a kid my dad caught a mitten crab in the delta (invasive freshwater species) and gave it to me, I kept it in a 20 gallon for I believe like 2 years??? It was an awesome pet and I have been feeling nostalgic.


SO tdlr: Is there a kind of crab I can keep in like a 3 gallon tank on my desk, stocked with live rock and live sand with no heater and just a tiny hang on back filter? (maybe even no filter?) Can I keep like a pair or hermits this way maybe? (I would like a shelled crab though)

 

[Bigpapii]

Live rock and sand wouldn't survive as well in an ingested environment
If you want an easy low maintenance tank you can go with the freshwater fiddler crab
No worrying about salinity.
Oh and they can live in waters around 74-80
So room temp water will be fine however I'd still get a mini heater like this

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