San Francisco, CA
I use to work for Yum Yum fish and so did one of my friends.
3 words of caution: MASSIVE RODENT PROBLEM.
The place is not sanitary and a lot of the stuff is contaminated.
Before closing every night the boss puts out some rat poisoning onto some avocados on a tray. In the morning, they wash off the rats droppings (which is everywhere) on the floor but they don't clean the container area and the cloth that is used to wipe the bowls and sushi plates, more than once, I've seen rat droppings in the cloth bag.
I'm honestly surprised that no one has gotten sick yet. Aside from the rats, there are also a lot of flies and the overall cleanliness of the place is almost none existent.
Yum yum fish use to be one of my favorite places to go to but a few years back, they changed owners and it has gone down hill from there.
The sushi is good but after working for them, I stopped eating there. Thought about reporting them but didn't want to get into the mess.
If you value your health, eat elsewhere