how long?

  • We are currently upgrading MFK. thanks! -neo
Most of what is labeled as ghost shrimp are freshwater.
 
Ghost shrimp are sometimes acclimated to SW and fed live to SW fish. I don't know if they can live a long time in SW, but they can live for a while at least (even though they're generally FW - there are actually multiple species of shrimp that are sold as ghosts). I once saw (at the LFS) a few ghost shrimp swimming around in a tank as feeders for a small octopus. It was pretty cool - I watched as he snuck up and caught one.
 
Ghosties are hearty and can handle a wide variety of conditions.

I had a 10g tank with a snail problem I didn't want and I wanted to experiment a bit in getting rid of them. So I took the fish out and dumped a half of a large aquarium salt container - about 30 oz/what's that about 900g? - in the tank to kill the snails. But I also had two ghosties in there to see what would happen.

The snails were all goners in about 6 hours - the water was swirly like gasoline fumes it was so salty - and the ghosties lived over another week before one died - keep in mind, I wasn't feeding them much either.

The salt did wonders for the algae that was starting to take the tank over too.

Since then I learned how to tolerate and/or control snail populations a little more rationally, but lessons were learned and cruel fun was had...

I eventually removed 90% of the water and did two more changes before putting fish back in but I wouldn't put anything past a ghost shrimp. They are tough. And http://www.monsterfishkeepers.com/forums/showthread.php?t=46604 dangerous!!!
 
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