what happend to my fish

[bmw318is]

OK. I woke up yesterday morning roughly about 24hrs after I purchased my first fish for the tank. I did a drip for about 1 1/2 hours before putting the lil guy in the tank. The tank has been up and running for 3 week with LR and tank vitals were great other than the water salinity which was a little high. The Pseudochromis seemed to be doing fine, I.E. normal behavior.

But I woke up to find my Pseudochromis thrashing about in the tank it almost looked like he was having trouble breathing I moved him to a QT and found that he was missing half of his tail?????

The only other inhabitant of the tank are some small hermit crabs. before going to bed I found what looked to be the remains of one of my 10 crabs. I am down to 9 as of this morning. I am afraid to say that I may have a hitchhiker and I have an idea of what rock it lives in but I have no clue what it is. the rock has about 10 to 15 holes that are all connected from what I can tell because the Pseudochromis was swimming in and out of the rock from all sides. I took the rock out of my tank last night and looked over it as best I could, I found nothing.

Please any advise would be appreciated.

[dannable]

I would wait until dark and take a look with a flashlight. I have heard of other people in this forum doing that.

[techreef]

if there's no life on the rock that you're concerned about keeping, dunk the entire rock in FW and see what comes climbing out. if you can't dunk the whole rock, pour plain seltzer water in each of the holes. it does a great job of driving out pests.

[bmw318is]

i'll try the FW dip tonight

[bmw318is]

One more thing i never found the shell of the missing crab just a few of his legs????

[Sk8r]

Be sure you're not conned by crab molt: they shed their shells, and it can look pretty much like a dead crab even on close examination.

A flashlight tour is a good idea.

[Shagsbeard]

You've got a nasty predator in there. My guess would be crab or a mantis shrimp. The problem with these guys is that they've adapted to not get themselves into trap situations. Trapping one is really hard to do, but it's worth a try. There's designs for DIY mantis traps, and you can buy them commercially. It's probably worth a try before you move on to freshwater dipping each rock, and sifting through your sand bed trying to find the guy.

Curing any live rock... even if already cured can help find these guys. Adding more live rock to an existing tank should be done with utmost care. Observing the rock in a quarentine tank for at least 24 hours is a great idea.

[bmw318is]

I know for a fact that its not crab molt one there is no shell and two all that was left was 3 legs and one claw it looked like a murder to me!

[Myrphie]

That's fairly common for hermit crab molts. ^^^

[davocean]

Crab molt doesn't explain the pseudo though.
Flashlight search.

[bmw318is]

Ok just went home on my lunch and did FW dip nothing?
I did find the empty hermit shell