Port

Unlocked at town level 3, the port is divided into four sub-tabs:

Port
Sell materials, energy, food, and iron for money. When resetting ("claim fee") at the office, your resources (except technology) are automatically sold.

The resource value is based on the current resource production and income. In particular, increasing the income increases the value of the resources, while increasing the resource production devalues the corresponding resource. Each resource is worth 12.5% of the total income. If all resources are sold, this means a 50% increase in effective income (62.5% once you unlock the airport).

You can increase your port level with iron for a x1.25 multiplier of all profits per level. The first level costs 1T iron and each level costs 100 times more thereafter.

Ship Missions
At city level 14 the player can send ships on missions to gain Pearls. These can be spent in the marina, the aquarium, and the souvenir shop. Each mission initially produces pearls equal to the number of hours of that mission (this can be increased at the workshop after unlocking Holyday Island). The three mission types are: Island (4 hours), Lagoon (8 hours), and Ocean (12 hours). Ship missions, pearls, and everything acquired with pearls persist on resets.

Marina
At city level 14 the Marina opens to allow you to spend pearls earned during Ship Missions on marina items. There are 12 marina items that have to be bought in this order, the bonuses of all items are added.

Aquarium
After earning all marina items and 500 additional pearls, the aquarium unlocks to allow the purchase of aquarium items. The pearls stay available - there is no fee to unlock it. There are 60 aquarium items. Their price starts at 60 and decreases by 1 until it reaches 25, afterwards their price increases by 1 again. Once you have bought all 60 items, you can continue to increase your aquarium level for a small addition to the "all profits" multiplier. Each additional level costs 72 pearls for an additional +50% (+3875% total after the first additional level, then +3925% total, and so on).