Aqua Laguna

Aqua Laguna (アクア・ラグナ, Akua Raguna) is an annual high tide that happens in Water 7. It engulfs the lower part of the city with a very big wave. Every year during the Aqua laguna everyone needs to move to a very high place. After each Aqua Laguna, part of Water 7 sinks. This causes the city to constantly have to be rebuilt. In an anime filler episode, it was shown that on the roof of the houses in the lower part there will be salt which is known as the salt from All Blue.