Dead Blue Velvet Shrimp

[Guest141771]

I checked my tank yesterday, found a blue thing there and assumed it was nothing. I looked again and found it was a dead shrimp!
I am not sure if this was a result of old age, or a disease of some kind. Should I be concerned?

 

[Guest141771]

Second one died today, so something is going on. I will try to test the water perimeters soon