Where I live, people usually suck the bowl through or dump it out and pack a new one when it's mostly black and getting ready to turn grey. Some rich kids I know dump it out with a little brown. Greens obviously gets you a lot higher and smoked bud tastes kinda gross after a while.Lately, I just smoke it until it is just a little grey... I don't rip it after it's black though 
When do you cash out your bowls? I know a lot of people who say 100% grey ash first.

When do you cash out your bowls? I know a lot of people who say 100% grey ash first.