Crabs and fish choice????

You basically need reeeaaallly big fish, and even then the crabs wil do their best to prey on them. The ironic thing is, if the fish is large enough to avoid predation, they generally will eat the crab/crayfish...

There are a few exceptions, like large catfish, but generally, any setup you do have with crabs may work for a time, but eventually the crab will grow and the fish need ot sleep (usually near the bottom of the tank).

There may be a mix that works, but I do not know of one. The only setups I know that are sucessful are very rare as it is built on individual crab behaviors (in this case low agression personalities and kept overfed) and kept with mature large peaceful cichlids. every know and again they have a fin shortened though! :eek:
 
With crabs, many also say they need brackish water to live a full and health life. The also need an air-tight lid to prevent them walking across your living room floor. IMO too many reasons not to keep them unless you build a crab only vivarium (they need dry land as well otherwise their shells can become to soft from being underwater constantly).
 
I like the crabs or shrimp in a species only tank. To many chances for things to go awry and lose all your work.
 
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