We use Safranin O, 0.1-0.5% in water, and I diluted it out further,
so it was more like 0.05%.  Dip the slides in filtered stain, rinse
with two changes of water, air dry and coverslip.  to remove excess
Saf O on the chance it is too dark, use 70% ethanol or adjust stain
time for darker or lighter.

Reference:  BioTEchniques 23(4): 642, 1997  Ho and Lin, Safranin O
counterstaining enhances the counting of B lactosidase expressing
cells.

We have lungs beta Gal stained whole mounts, fixed and cryoprotected, did
frozens, air dried and this counterstain, the results were brilliant,
with individual cells crisp blue against the counterstain.  Nucleoli
are brilliant red, cytoplasm and and nuclei are light red.  It works
on both sections and cultured cells (chamber slide preps)

Happy Thanksgiving

Gayle Callis