Probably not needed. They have a room that faces the animals. It's a nice view but nothing special. It's not like you're right on top of the animals or anything. You're 2 stories up, and the animals are off in the distance. They have a row of tables along the windows, and more tables in the middle. I'd say it's about 30 tables. If that's full, they have more tables in a room before that.
The food is great, I had a pasta dish and the wife had a fruit salad. If you think it's going to be busy, show up at 11:30am. That's how you beat the crowd at lunch time. By the time the food comes out, you'll be hungry.