[No Spoilers] (3rd repost because I forgot a S in spoilers). Due to the genocide of the bladderfish population I have taken the survivors and initiated step 1 of Project Bladder

One three-column containment unit solely for Bladderfish.
Another for Reginalds.
That sustained me all the way through my first playthrough.

Before finding the containment unit, I'd regularly rotate which cardinal direction I would swim in to gather bladderfish.
I actually wasn't sure whether overfishing had any in-game effect at that point; it was more of a roleplaying decision.

Once the three-tier tank filled up, taking my daily water needs wouldn't dent the population and they'd replenish very fast.

It was so convenient that, even after I found the water filtration device schematics, I'd keep lockers full of bladderfish water around for general day-to-day hydration.

The large filtered water would be reserved for long-distance expeditions, when the space saved by 50-unit vs 20-unit water bottles would become significant.
This ended up being overpreparation -- I ended the playthrough with a few hundred large bottles left over, despite being very lax about checking my three filtration devices.
I had also set aside about ten times more Cured Reginalds than I'd actually consumed over the course of the entire game.

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