I'm gonna jump all over that because Hydrated lime is dirt cheap. You could dump a tremendous amount of Alum in 7.4pH water without killing fish.
For every 35-40$ of Alum you use a buck or 2 of hydrated lime.
PPE is a part of this, if you're careless you should be hiring someone else anyway, and with all due respect, 50% of the time doesn't compare to near 100% of the time.
I know I sure don't have time to keep doing it over and over.

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