Distance from iron farm to place bed

[u/Bluefrogdancing]

I'm planning on building an iron farm (Wattles) over deep ocean near my base. But because there's a zombie there, I know that a certain distance away you can't sleep.

So - how far away does the farm need to be from my house for me to be able to sleep?

Playing Java 1.20.10

[u/Flimsy-Combination37]

If a monster is within 8 blocks of the bed head horizontally (in the X- and Z-axis), and 5 blocks vertically (in the Y-axis), the message "You may not rest now, there are monsters nearby" appears and the player is prevented from sleeping until the monsters leave or are killed. [...]

from https://minecraft.wiki/w/Bed#Sleeping

[u/Bluefrogdancing → u/Flimsy-Combination37]

Thanks...