Can't keep ornamental shrimp

I'm thinking that one or more of my fish is eating any ornamental shrimp I put in my tank. I had a pair of cleaner shrimp for years and then they both eventually died. Since that pair died I've tried replacing them with skunk cleaners, peppermint shrimp, and fire shrimp with no luck. I acclimate them properly and watch them swim around and eat for the first day or two after I add them, but then overnight they disappear.



I have a 93 gallon cube tank with the following fish:

2 ocellaris clownfish (2" and 3")

1 engineer goby (8")

1 clown fairy wrasse (3.5")

1 dwarf flame angel (3")

1 tomani tang (4")

1 Randall's watchman goby (2.5")

1 starry blenny (2.5")



I have a pretty standard cleanup crew with the largest hermit crab only being about 0.5" maximum. I don't have any other invertebrate that might be the culprit.



I'm guessing it's either the wrasse or the engineer goby that's eating them. Do you guys have any other ideas? I really love how the shrimp used to hang upside down under my cave and jump on my arm to clean me when I had to do maintenance. I would love to add them again. Catching the culprit if it does end up being a fish will be next to impossible, so this question is more just for peace of mind than a solution unfortunately.