Somethings Killing my shrimp

Nitrates should be <10. They aren't as toxic as nitrites and ammonia though you have to be very careful as high levels will kill fish, inverts etc. Corals and Tridacna's especially require nitrates for feeding of zooxanthellae.

 

When I had taken my water to the lfs they told me that ammonia, nitrite and nitrate were at undetectable levels. That would mean near zero right. You know that they are in there.

 

I have also got a six line wrasse and when i bought a peppermint shrimp and a fire red shrimp, the peppermint was toast in about a week. The fire red is still alive but he will not come out of this one spot in the live rock. I even have to inject brine shrimp into his little hole to make sure he gets food.

He also took a big chunk out of my clowns tail. I think the six line wrasses are very reef safe but aggressive towards other fish and inverts.

 

Call me a weirdo but in my opinion, that kind of behavior would make them not reef safe