Why My fish Die?

Chris, Do you test for iodine?? I know if you overdose iodine it is not good especially for crustaceans. I am not sure how toxic it can be to fish.
I am still wondering about Nykademus's post about internal parasites or other disease. Some fish could be resistent to it but new ones would not be. This could explain why others with your water don't have problems and why we can't find a parameter out of wack enough to cause these loses.

 

If you are using a good name brand salt I would stop dosing everything unless you test for it regularly! Another rule of thumb for saltwater...don't dose anything you cannot/do not test for.