So my tank has been running for 4 months now and all levels are great! So in the last 2 weeks I have added a cleaner shrimp and a michaels pistol shrimp. Both have died within 36 hours. But I added a watchman goby with the cleaner and a sailfin tang with the michaels. And both fish are doing great! So what is the problem? The only thing I can think is my large emerald crab is killing and eating them but then again my michaels pistol shrimp was about 1 1/2 inches long so it should have held its own but idk. If anyone has any ideas please let me know. Thanks