Update- today was the scheduled day to take my Blue Throat trigger that has been in the QT tank for 6 weeks and put him into the display tank. Yesterday noticed he was even shyer than usual - he always immediately came out of the PVC as soon as I put food in the tank and fed voraciously. But yesterday he didn't - but he did eat , and today I found him dead. So here the question = WHAT HAPPENED?? checked the ammonia and nitrate= both zero. HE never acted like any trigger I had ever seen- none were ever shy like this guy. So was he sick the whole time and/or never recovered from the ice cold trip he had 6 weeks ago upon purchase and the poor communication with the Seller, ups not ringing the doorbell,etc. Should I have treated him with meds even though he ate well and no sign of disease? I am at a loss.
Frankly , I have never had good luck with the QT scenario and have always had better luck with just good observation at the store and not buying any fish that I am not confident in. However, with the new tank I figured I would be extra careful so set up a new full tank setup fro a QT = 40 cube tank, hang on skimmer, programmable wave pump, etc. Did water changes diligently, etc. - spend more cash to a " higher grade seller" and ended up with not a single fish going into the display.
So, I guess next step is to buy locally and medicate fully immediately and do the program of hypo salinity .... OR just say forget it and not add more fish.