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Ocean Doors and Seashell Fencing are two items you need as part of the storyline in Pokémon Pokopia's Bubbly Basin.
They are required to build the Ocean Temple as part of the Build the Beautiful Building quest step. Chances are you haven't encountered either of these items yet - but the good news is both are easily within reach.
This guide explains exactly how to get the Ocean Doors and Seashell Fencing required in Pokémon Pokopia.
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How to get Ocean Doors in Pokémon Pokopia
Ocean Doors can be crafted with a recipe - the location of which is on the site of where the Ocean Temple is being built.
Clear out the blocks that are covering the proposed site, and you'll uncover the Ocean Doors recipe along the way. For us, it was towards the back in the middle - the below screenshots will show where:
From there, you need to craft two Ocean Doors at 1 star-spotted rock each.
How to get Seashell Fencing in Pokémon Pokopia
Getting Seashell Fencing is even easier. Head to the Bubbly Basin Pokémon Center, and interact with the PC. Then, as part of the Environment Level 3 rewards (you'll have reached this in order to unlock the Build the Beautiful Building quest), you'll unlock a recipe for making Seashell Fencing.
Purchase it, then head to a workbench. From there, you need to craft 10 Seashell Fencing at 1 star-spotted rock and 1 Shiny Pearl each.
If you are struggling for Shiny Pearls, remember you need to grab Grubby Pearls, then scrub them clean.
Best of luck with the rest of the Ocean Temple build! There are a number of Pokémon you also need to recruit - one of which is Frillish, who is found in a cave nearby...