

Squid can be killed by asphyxiation if they get out of water. As with other farms, it is important to kill the squid quickly to allow more to spawn. Thus on a multiplayer server, if any player is near an ocean, it will effectively block output from your squid farm. There is a separate mob cap for water mobs (this doesn't include guardians), but the mob cap is shared among all players on a multiplayer server. To have a better spawn rate in your farm you have to eliminate water blocks between 50 and 62 layers in a 128 block radius around the player and at least 24 blocks from the spawning area of the farm.

Since 1.13.1, they now only spawn in river and ocean biomes. However, they will only spawn if their spawning block (the solid block underneath the water) is between Y (vertical) level 50 and 62, inclusive. Note that downwards columns do not pull the squids, making them considerably less useful for squid farming. Squid can also spawn in bubble columns, (Bedrock Only) so an upwards column may be used for collection. Squid will spawn in 1 or more blocks of water, no matter whether it's a water source or flowing water.
