Aqua affinity is a unique enchantment in Minecraft that makes it, so players don't suffer any mining penalties when trying to mine blocks while either floating in or underwater.
Usually, players will suffer a small time delay to destroy blocks when mining without an aqua affinity enchantment item. But if you grab yourself an armor piece enchanted with aqua affinity, you will be able to mine at a faster rate while floating and in the water. In turn, aqua affinity also makes it so it's easier to get blocks you can only get underwater.
So, if you are interested in this enchantment for whatever reason, the best way to get it would be to make books and then an enchantment table. You will then need to make 15 bookcases and place them around the table with a one-block buffer zone between the 15 bookcases and the table.
When you are done, you will need to use both books and lapis lazuli to make enchanted books until you get the aqua affinity enchantment.
You can also use fishing poles to get an aqua affinity book, but you will need to get both the lure and luck of the sea enchantments on the fishing pole.
Trading emeralds with villagers and loot enchanted books out of dungeon chests to get aqua affinity books is also an option. But overall, we recommend either the fishing pole or enchanting table routes as the best options to get the book.
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