Minecraft – How should I fill a tank

minecraft-java-edition

On a floating-island challenge map I'm making a giant tank of water to try to get squid to spawn. How should I go about filling it; top-down or bottom-up? What's the quickest method to have it all filled with source water so I don't have strange currents in it?

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Best Answer

Keeping in mind my own observations on squid: it seems as if squid are perfectly capable of spawning in 1 block deep water (reference); you might be better served with a huge, shallow tank than a large, deep one.

Filling a huge, shallow tank is very, very fast; place source blocks first along one edge, and then along another, nonparallel edge, and you're done.