Stop using spotone.
Try www.veronicacass.com and order her dyes instead. I've used them for years and never had problems. I use them on the negative as well as the prints. The bottles are about$4.00
Probably all you'll ever need is mauve (believe it or not), which I use for almost everything. I also have midnight occasionally, as well as browntone for sepia and selenuim toned prints. You use them the same as spotone but they blend better and soak in better.