A very interesting seed that generates ocean ruins on land. You will appear on a small island next to such a structure, nearby you can notice a group of turtles. Submerging under water, you will find even more ruins, while several chests are hidden in them. You should search carefully, a lot of drowned are floating around. You can also go west and at coordinates -680 ~ 300 find a rather large mushroom island.
How to use Sea Ruins on Land seed
Start the Singleplayer mode
Select ‘Create New World’
Then click on ‘More World Options…’
In the ‘Seed for the World generation’ field, enter 519124461