New tank but crabs are dying

[Bob Escher]

Hi all
I have had this tank running now since early Dec. I waited tested and tested when things seemed to be fine ( water parameters) I put in several snails (Nassarius ) and red leg hermit crabs.
I was told that the cycle wasn't complete although I did have beginnings of algae on my dry rock. ( I have 4 lbs of live rock) and maybe three of dry. I also added food, a shrimp and bios spiral to help cycle the tank.
This is a ten gallon tank that was going to be my QT tank but changed my mind on it for the moment.
I lost two red leg hermits today and can't find the snails) when I had explained that I had snail last week it was suggested that since the FULL cycle wasn't done go ahead and do a water change. I did
I have a sponge filter in it, a HOB filter when biomedia and ammonia filter in it.
Aqueon light that is a Led with grow light, blue 20 inches long
I have Cribsea sand it appears to be the smallest grain and it was live sand as well
Heater( temp is: 77.8
So here are my parameters
Ammonia: 0
Nitrite; 0
Nitrate: o
Ph: 8.3
Salinity: 1.240
I have added Kents purple to let corraline grow
But that's it other than the above
Should I just watch what I have left and to not add anything more for another few weeks but add something to see if the cycle truly is not over


Thanks

 

[Diesel]

Your salt is correct at 1.240 or do you mean 1.o24?
Besides the question on your salt you might have a toxin in your tank.
Maybe the dry rocks came from a copper treated tank.
Your test # look ok, nothing that I can see why your crabs and snails are dying.

[HASHTAG]#reefsquad[/HASHTAG]

 

[Bob Escher]

Sorry meant1.024
Hmm I have to get a copper test kit. Some came from my LFS and Petco and the tanks that it came from had crabs in them.
I also use RO/DI water although it's well water cause it's had water KH was at 11 after running through the ro/di unit

 

[Diesel]

Sorry meant1.024
Hmm I have to get a copper test kit. Some came from my LFS and Petco and the tanks that it came from had crabs in them.
I also use RO/DI water although it's well water cause it's had water KH was at 11 after running through the ro/di unit

That would work.
Get [HASHTAG]#reefsquad[/HASHTAG] and @Randy Holmes-Farley in here on recommendations on what kind of copper test kit you should get.
I send my water in once a month to Triton which tells me in one view what I'm lacking or what is to high on the bad stuff.

 

[kschweer]

The hermits may be a coincidence. You said you put in nassarius snails, they burrow into the sand bed. If you look close you may see a small tube looking thing sticking out of the sand, this is the snail. You can also try feeding the tank a little and the may come out or wait until night time when they are normally more active.

 

[Triggreef]

Sorry meant1.024
Hmm I have to get a copper test kit. Some came from my LFS and Petco and the tanks that it came from had crabs in them.
I also use RO/DI water although it's well water cause it's had water KH was at 11 after running through the ro/di unit

Hmm.. Your dkh is 11 after the ro? That's before salt or after mixing? What kind of salt are you using? What are you using to test sg?