I've been replying on your other threads, but now I see that you actually lost the threadfin (Meowzer, this is a Threadfin Lookdown) and the yellow tang.
My thoughts:
Tank got stirred up and went into a mini cycle during the move.
Yellow Tang and Threadfin shouldn't have been in that size tank to begin with, and if your LFS sold you these fish knowing what size tank you had, then I wouldn't trust another word that comes out of their mouths, including what your water parameters are. Go get yourself test kits, API is the standard and usually available everywhere and easy to use. Stay away from Red Sea kits. API has two salt water kits, a reef master and a salt water master, you're probably going to need both. Or you can just buy individual tests of whatever doesn't come in the one. Make sure you have a test for Ammonia, Nitrite, Nitrate, pH (high range), Calcium, Phosphate and Carbonate Hardness (alkalinity). Salifert also makes good test kits, but they're harder to find and more expensive.
What water and salt are you using for water changes and how do you perform said water changes?
My thought here is that the fish were too large for the tank and between the stress of a small tank and the stress of a move, they could not take any more.
I don't care that your LFS told you that your water was perfect, if you lost two fish and a shrimp in less than 36 hours, your water is not perfect and that should be a red flag not to trust them.
You need more filtration and water movement, which can be a challenge in a bow front tank. What size is the Hydor power fan?
You mention rock, which you need more of. What about substrate, is this a bare bottom tank?
You need more of a CUC if you're going to have more fish.
Get a refractometer, hyrdrometers are inaccurate. If you're going to keep inverts, you MUST know the exact salinity level, not a guesstimate of what your hydrometer is going to give you. If it's a swing arm, THROW IT OUT.
Please keep an eye on your anemone, if you've had fish and shrimp die unexplainable deaths in a short period of time, your anemone could be in trouble. They require pristine water quality and if it dies in your tank, you're going to have an even bigger mess on your hands. IMO, 8 months and then a tank move is not good for an anemone, the tank is really not stable enough for you.
