There could be any number of reasons they are dying. If its a 10 gal
, I would be careful about over crowding. How often do you feed? Do you track your water parameters? What were your water parameters last time you tested? is your local LFS
a privately owned retailer? Or is it a large company? large companies typically use one big Eco system, becareful about getting fish on a connected system, if one tank has ich, they all do. Do yo take your time with acclimation? Should take about an hour if not more. I don't use a qt either, the only time I have caught ich was when my fish were purchased from petco. They used one big Eco system, (are their tanks are connected). I prefer to buy my fish from a private retailer who has all separate tanks. Also, with live rock, I'm assuming you don't use copper to attack your ich, it takes about a month for ich to starve out. I personally would wait two just to be safe.