Can Ghost Shrimp kill Corys?

[Jonatheber]

I have a 46g bowfront with a bunch of livebearers and (until 2 days ago) 3 cory cats. The water is 33% changed weekly, and has 0 ammonia and nitrite, and 20ppm nitrate. The corys have been fine for months. I purchased a few ghost shrimp to try to help out with some cleaning of the tank (e.g. hair algae) and 5 cardinal tetras to try to brighten up the bottom 1/3rd of the tank. The cardinals all died within a few days - I have high pH, and that probably did it. 48 hours later, overnight, all three corys died. There are no signs of any distress from any of the mollies or guppies or the lonely painted glass tetra in the tank.

Is it possible that somehow the ghost shrimp killed the corys??

 

[libertybelle]

Can you post pictures of the shrimp? There are sometimes various species mixed as ghost shrimp and some are predatory.

That said, I think it is probably more likely that the dying fish caused a transient ammonia spike which killed the cories.

Increase your feeding if you are unsure. I have whisker shrimp (one of the predatory species, bought as ghost shrimp but definitely not ghost shrimp) in my quarantine tank being quarantined for worms etc before moving to other tanks. It’s being treated with paraguard and maracyn. I had two cories (one a panda and one a Pygmy cory) that I realized were ill while the tank was still filled with the ghosts and whisker shrimp. These fish needed treatment fast and I didn’t have another place to put them so I added a bunch of moss as cover and crossed my fingers and added them.

Here was my mistake. I didn’t feed the tank first. Both the ghosts and the whisker shrimp converged on those fish like fricken lightening. I instantly realized my mistake and added pellet food and as fast as it had begun the shrimp moved on to the pellets. At the end of the day I guess they are lazy. I made sure to keep them well fed since then and they don’t bother to hunt even if they *can*. Both cories are doing waaaaay better with treatment and as long as the shrimp aren’t ravenous, they leave them alone even though they’re still pretty weak.