Problem with skunk cleaner shrimp

Hey guys, I am not sure why this tank has given me a bit more trouble than usual. (maybe it's because I'm not next to it 24/7 to find a problem when it arrives).

So the problem I am having is that so far all the shrimp that I've bought have died. (4 total). First I bought a pair, and they lived for at least 3 weeks before one died. Then a few months passed and I decided to buy 2 more. One disappeared a week later. Then like a month passed and my oldest shrimp disappeared. Finally, a week later after that one, the last shrimp disappeared.

I have no idea what's going on.. There is no trace of the bodies at all. I have a bunch of hermit crabs in the tank so maybe they are eating the bodies before I get the chance to see them.

My salinity is 1.024 and I acclimate them for at least 1 hour and a half before adding them to the tank. I don't do drip acclimation but I add small portions of water into the bag every 10 minutes or so.

All of the other parameters test good. This tank is 8-9 months old now.

The only theory I have, and it is a very weak one is that we added a pretty gigantic Hermit crab to the tank. Could it be that he is killing the shrimp? I figured if the shrimp decided to molt, he might have taken advantage and ate them? I'm not sure how susceptible they might be when they are molting.

Any other theories? I really want to have at least 3 shrimp in this tank but I am afraid to add anymore until I know they have a chance to survive.

Ps. I ruled out copper as I have plenty of other inverts in the tank that are doing very well. Unless they are somehow resistant to it.

 

I would remove the"large" hermit.
Picture of the crab would help but if its large it is probably predatory.Large hermits don't need to wait for a molt.

 

I'm uploading a picture to photobucket now. He is pretty big. I just assumed that the shrimp would be a lot faster than him. He was in a tank that we tore down. Maybe I can set up a small 10G just for him.

 

This is him.

 

Crabs are mostly scavengers...I would be surprised if that was your problem.

As far as why some Arthropods would live (the crabs) and some would die(the shrimp) you have got me on that...

But I will say 1.024 is a bit too low IMO

 

Awesome zoa garden behind him!!!

 

Man how big is he? He looks monsterous!

 

This is absolutely untrue unfortunately.Large hermits can and do take down healthy fish and other inverts.Crabs are voracious and formidable predators.1.024 is fine IME.

 

I have to disagree with that. Crabs are scavengers but they will usually eat ANYTHING they can catch and kill including other crabs, shrimp, small sleeping fish,snails, etc. They are good hunters and capable of killing shrimp without a problem

^looks like Vinny beat me too it! Also concur on the 1.024 being just fine for fish and inverts, higher would be better for corals but not real significant for fish and crabs.

 

I would.He's cool.....8)