Betta and Crab?

[Aquarius Keeper]

I have a male and female pair in my community tank (Venus & Neptune -they get along great - there's plenty of room for both) and another male (Mars) in a separate tank.

Until tonight I had him in a one gallon tank with an air pump/filter - but he just seemed unhappy and the water parameters shifted too quickly, so tonight I put him into a 2.5 gallon tank, with the same air pump/filter (rated for 3g) - he's much happier and I'm wondering if I might add another small critter into the space. Not a fish - either frog or a crustacean. I know a ghost or cherry shrimp would be an obvious choice but I'm just curious if anyone thinks keeping a single fiddler or red claw crab in the same tank would be a mistake?

Thanks,

Jonathan

[onefish2fish]

i am unsure however my best guess would be no.

fiddlers are brackish (pretty sure)
but regardless they may nip the bettas large fins and also they need a sloped piece of land to get out and completly dry out.

cherry red shrimp are totally awesome, whats wrong with them? lol