Sorting big cells on FACSAria!

Dear experts in flow sorting:

I am trying to sort HUH7 cells GFP (brigth and not so bright populations) Just
two gates in a single color FL1 vs SSC (very simple sorting should be). Those
are big cells so I tried with the 70um nozzle but with medium pressure. I
haven't had problems with settings, or with accudrop. However, I couldn't have
pure populations. When setting the streams I can see the two perfect dots on
the camera on the screen and accudrop run perfectly, but when I am sorting I
don't see but a smear of white dots to the right and to the left of the main
stream (is that because of the big cells?). I am planning to try the 100um
nozzle, but can I run the accudrop with this nozzle eventhough they are very
small? If somebody can give me some tips, I will be very grateful.
And another question, if I prepare the machine for asceptic sorting, can I run
the accudrop before or I need to prepare a sterile solution of these beads or
run them after asceptic cleaning and then run again bleach and water for a few
minutes to keep the "sterility". (We do not have the FACSAria in a BSL-3 lab
yet)
Thanks a Lot
Vida