For now, just use plain 6% household bleach (no flavors, scents or gels, PLEASE). Just use 2x as much as you would pool bleach.
Regarding Walmart pool chemicals -- I hadn't checked them out for several years, till just the other day. Long story short: Walmart has gone over to the 'Dark Side' with their pool chemicals, and is totally a BioGuard / Chemtura mind-slave.
You can still buy 'bleach, borax and baking soda' there, and they now are selling "washing soda" = pH Up. But their algaecides and sanitizers are AWFUL.
I need to write a post about this, but I just haven't gotten around to it.
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