Under the sea money is not used, instead they use the trading of food. The most common thing to trade is the hamburgers. The money is only used with other countries to import stuff like the ingredients and other city-based stuff, but inside Burger land no money is used. It depends on the value of the thing you want to get on how many hamburgers you need to pay.
In Burger land everyone believes in The God of Hamburgers. There is a lot of theories about this god. The fish believe in many different theories but the most realistic one is a theory that says The Hamburger God was the best chef in the whole ocean. Since Burger land's economy is based on hamburgers they believe in The Hamburger God.
There is different climates under the sea. Burger land's climate region is obviously a sea. Under the sea there is only two climate changes which are Summer and Winter. Everyone is happy when is Summer but when it comes to Winter a lot of fish have come to struggle. Under the sea the temperatures during winter become extreme since water is a lot more colder than air. The temperatures affect daily life a lot because during winter the hamburgers sometimes do not cook how they are supposed to.
The only thing fish are worried about are sea-bears. But fish have their own protection method of protecting the city, they made a huge circle surrounding the entire city. Sea-bears cannot enter the circle but there has been sometimes were the circle gets erased in some parts. For the most parts citizens feel safe with the circle. But if they need any help they just need to ask for a stick to draw a circle around them and protect themselves against the sea-bears.