DAE remember when we all thought 20 volume developer was for everything?
I was mixing 20 vol for a level 5 to level 9 lift for almost 3 years at my first salon in Mesa until a color educator asked why I was processing for 50 minutes and I just stood there holding my brush like a fool, so now I'm curious what outdated habit the rest of you had drilled into you before someone finally spoke up?
Plenty of people in this business use 20 vol for almost everything and their clients are just fine. The real issue was your timing, not the developer. Fifty minutes was the mistake, not the 20 volume.