Need some Help

[hink]

That's why I am here Frogger and Dkokoman there is a lot of information that I could spew on here but it doesn't do any good if it isn't focused important information I don't dose salinity is 1.025 I have an auto top off to keep it there I test ammo nitrate nitrite ph calcium phos weekly. I mentioned how long I had the fish for in the post clown fish a pair for 3 years 6 line for 2 the blue green and the black bar are a year old. I have not added anything recently. I QT the fish 4+ weeks before I add them to my display tank. I did not do anything to the tank no additions just a water change with RODI water as I do every week. I did not find the bodies tried to find them but could not (I have a good clean up crew). I have checked behind the tank around the tank and everywhere the overflow the sump (they cant get to the sump with my overflow they can get into the overflow but they cant get down the sump and I can see them if they are in there have a couple of crabs camping out right now in there. The fish were eating before they died had mysis shrimp even the day before (the 6 line) the clown the day of was just pellets. I check the ammonium levels weekly every Friday. I know sometimes fish just die we do not know their age but within 2 weeks? it just seems to be too much of a coincidence and I just cant live with that. The remaining live stock are swimming around and happy eating lots fed them mysis yesterday and pellets today. temp in the tank is 79-80.