Does it have to be bright or dark?
~ @Muunkee
i ripped this from the wiki clearly i was just wrong;
Squids will spawn in 1 or more blocks of water, no matter whether it's a water source or flowing water. The level of light is not important. However, they will only spawn if their spawning block (the solid block underneath the water) is between Y (vertical) level 46 and 62, inclusive.
To have a better spawn rate in your farm you have to eliminate water blocks between 46 and 62 layers in a large area around, or build it artificially in a desert or any place without superficial water in a large area.
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. Thus on a multiplayer server, if any player is near an ocean, it will effectively block output from your squid farm. As with other farms, it is important to kill the squids quickly to allow more to spawn.
