Why do my Hermit crabs/shrimps keep dying?

[jiffyjhn]

The small crab is slowly going back into his shell. The larger one is still alive(poked it with a toothpick and there was movement).
Is it ok if I kept them in the cup and float it in the tank overnight?

 

[Cantusaurus]

the salinity in the tank is 1.025, I have another established tank that I borrowed a hermit crab from. that tank has 1.021 salinity.


Salt mix is Reef Crystals. I have a 5 stage spectrapure RODI unit

Oh, I see. Yeah I guess that is a big salinity difference, but you did drip for a while. Maybe it was not quite enough, but it is hard to pinpoint the exact reason. Reef Crystals is good. Especially for the price. The mix also has high parameters (Alk, Calc, Mag). So I doubt the tank had an insufficient amount of the elements. Definitely strange as to why they did not do well. Most likely bad luck and it being a newer tank ;/

 

[fachatga]

That’s a big jump in salinity for a short acclimation time especially for an invert

 

[jiffyjhn]

Oh, I see. Yeah I guess that is a big salinity difference, but you did drip for a while. Maybe it was not quite enough, but it is hard to pinpoint the exact reason. Reef Crystals is good. Especially for the price. The mix also has high parameters (Alk, Calc, Mag). So I doubt the tank had an insufficient amount of the elements. Definitely strange as to why they did not do well. Most likely bad luck and it being a newer tank ;/

The large Hermit lived in my established tank for 4 years. I barely even do water changes in that tank(15% every 3 months or so). The parameters in the new tank is better(much lower nitrates)

 

[jiffyjhn]

That’s a big jump in salinity for a short acclimation time especially for an invert

yeah probably should have dripped for longer(3+ hours)

 

[fachatga]

For that jump it could take days. Better not to share livestock with such different salinity IMO. Probably not worth the trouble or risk

 

[jiffyjhn]

LFS near me all have low salinity 1.021 - 1.022. I Guess this means I shouldn't even buy inverts from those stores. or lower my tank salinity?

Actually I should probably check the accuracy of my refractometer. Maybe it's off and the LFS is something like 1.025, which would mean I'm closer to 1.030

 

[fachatga]

Guess you’re kinda stuck. If you want corals you’ll need the higher salinity. Just take it really slow. Probably expect a few losses. Do your best. You’ll get the cuc going. Don’t let a few losses early on discourage you. Sometimes it seems like nothing we can do will make crabs live. Sometimes it’s like they’re made of steel.

 

[jiffyjhn]

Don’t let a few losses early on discourage you. Sometimes it seems like nothing we can do will make crabs live. Sometimes it’s like they’re made of steel.

Thanks. I feel better. Felt bad cause I kept killing these little guys.

 

[fachatga]

If there’s a reefer on this site that hasn’t killed crabs and snails please step forward. Think I hear crickets. You’re not doing anything wrong. Take all this advise as help to get better. Nobody’s perfect. You’ll get it to work.

 

[jiffyjhn]

update:
I put the large hermit back in the tank on a rock. He started walking around. the blue leg that's out of the shell is still clinging onto his shell but still not going inside. the other blue leg that was lying upside down flipped himself over and is picking stuff from the sand bed

 

[jiffyjhn]

The large hermit ended up dying a day later. I can no longer find the hermit that is out of shell.
I added few more and did slower acclimation(3+hours) and no issues.
In conclusion it was the acclimation process and not starving that caused them to die.

 

[diver22]

One thing that they told me is that for inverts the salinity is recommended to be at 1.025 or 1.026, seems that you have it at 1.21 or so.

Also a 2 month old tank you will certainly have challenges, heck mine is 4 years and at times i have great challenges, different ones but challenges...seems Algae will get you one time or another...lol

 

[lynaea75]

In my experience hermit crabs have trouble righting themselves when they are upside down like that. Is the rock work/sand different in your smaller tank that they are ending up flipped completely over? Or maybe one of them is shell hunting and is flipping them and then they can’t right themselves. Regardless, if you see a hermit upside down or in a weird/tight spot for more than an hour it probably is stuck and needs assistance.

 

[jiffyjhn]

looks to be ok now. out of the 4 hermits I put into the tank. 1 is alive and well. The ones that died were likely due to drip acclimation being too quick for the salinity difference. Not planning to add any more into this tank since the Trochus snails can take care of all the algae on their own. Will do a long drip acclimation if I decide to add any in the future

 

[SlugSnorter]

1) Acclimated for about 1-1.5 hours using drip method. Though checking around on different threads, some reefers just throw them in without acclimation with no issues. I could try again with longer acclimation
2) there is still algae in the tank. some parts of the rock still has a brown tint to it.
3) the tank is brand new from FijiCube, I ran it for 2 days with RODI water before putting salt water in it to make sure it's clean. I have never copper treated any of the fish.

2 things,
1 check acclamation method the site recommends if you the ordered crabs

2 as others have said, if there isn't enough food you can drop a few sinking pellets if you are sure your crew is gonna get them

 

[Rick's Reviews]

Any upturned crabs still in same position after a day, just pick up and place to help little guys out...
Try something a little less pointy than a toothpick to check on movement

 

[PeterEde]

Just found my hermit dead on the sand bed out of shell.
He was in a week or so.
Parameters are spot on last test. Salinity is 1.025 and has been since I set up 9 weeks ago.
I have found other hitch hiker crabs dead also but the algae eaters are doing fine. Not found a single dead of those crabs including squat lobsters. there is plenty of food for carnivores in worms etc
I have 2 shrimp, peppermint and Bald shrimp and a number of babies from the bald shrimp who was carrying eggs.
Why the dead crabs while my longspine urchin was discovered as a 5mm dia who has lasted through tank cycling and now 20mm plus dia.
Why just certain crabs?

 

[Dburr1014]

1 and 2 were going to be my suggestions too and 3 is a good call.

I would lean towards acclimation or the copper just because you say they are dying so soon.

I thought copper also but... Snails are fine.

It's it possible the shrimp molted and your seeing the shell?

 

[Rick's Reviews]

Just found my hermit dead on the sand bed out of shell.
He was in a week or so.
Parameters are spot on last test. Salinity is 1.025 and has been since I set up 9 weeks ago.
I have found other hitch hiker crabs dead also but the algae eaters are doing fine. Not found a single dead of those crabs including squat lobsters. there is plenty of food for carnivores in worms etc
I have 2 shrimp, peppermint and Bald shrimp and a number of babies from the bald shrimp who was carrying eggs.
Why the dead crabs while my longspine urchin was discovered as a 5mm dia who has lasted through tank cycling and now 20mm plus dia.
Why just certain crabs?

Maybe your just feeding the inhabitants with new crab ? Just a thought.
do you have shells/ spare shells for your crabs to move into as they grow,?
So many questions and answers I assume will be mainly your aquarium is quite new, you may think your providing food, crabs do love abit of algae which I assume your aquarium has none