I'd say after it's done its job When I used Joe's Juice, I left the pumps off for about 10 or 15 minutes... but it starts "dissolving" before that time, IME, so it may be ok to restart the pumps earlier than that.
Hi Chuck,you've probably turned the pumps on already but a good tip for next time is to take a small siphon tube and syphon as much of the melted mess out as you can then turn the pumps on
-Liam.