My snubnose pompano in my 75 gallon saltwater tank just suddenly died

[GouramiGuy123]

I have a 75 gallon saltmarsh tank with some mummichogs, pinfish and some iverts. I also used to have 2 pompano that as of yesterday are dead for no real apparent reason. Literally 30 minutes before they were dead they were doing fine and had no issues what so ever (one of them had ich a while ago but had gotten better and was eating perfectly fine). Before they died, one of them was doing circles like crazy and kept running into walls and the decorations in the tank. They were wild caught but still they were doing fine up until yesterday. I am fairly new to saltwater but I have been keeping monster fish and more advanced fish for 5+ years now, what am I doing wrong?

 

[danotaylor]

Tell us about your water parameters and filtration.
What is your water change schedule?
Do you have a protein skimmer on the tank?

 

[Deadeye]

Open mouth deaths typically indicate mortality due to low oxygen. How is the surface agitation in the tank.
Disease can’t be ruled out either, especially with wild caught fish.

 

[kendragon]

My guess would be that they scared each other and rammed into the glass wall. Once they hit the wall, they lose their balance and die.