Sentimental Aquifer

Sentimental Aquifer is dungeon northwest of Exbel, under Mt. Skylift. After the final floor is the break point called Aquifer Crystal Passage, where there is a Kangaskhan storage. It leads to Sentimental Aquifer Depths. One must beat Lake of Acuity, Lake of Verity, or Lake of Valor to take on the respective trials that lie past that point. The weather here is always clear, and Golduck spawns, so if you frequently use weather condition to your advantage, consider using a weather rock.

Floors 1-30
The ground is a muddy brown, walls are rough, and a lighter brown around the edges. Floors are often very large and spaced, or either small with down to 1 room. Water is around the entirety of the dungeon.

Floors 31-60
The scenery stays identical, barring the walls, which are sharp and blue, and have bits of moss on them.

Aquifer Crystal Passage
The ending of this dungeon is Aquifer Crystal Passage. There is a Kangaskhan storage so you can retrieve a chain from one of the lakes if you didn't prior, so you can enter one of the trials beyond, in Sentimental Aquifer Depths.

Pokémon
''Pokémon in bold are recruitable. Please visit the Recruitable Pokémon page for more information.''

Dungeon Objective
Make it to Aquifer Crystal Passage to attempt the trials. Carbink is an exclusive recruit, and you can obtain a Cover Fossil here.

Tips

 * Every enemy Pokémon here is weak to the Grass-type, so using Grass-typed moves is a good idea.
 * Watch out for Azumarill though, it has Sap Sipper.

Trivia

 * Sentimental Aquifer was released on the 1st of June in 2018.