Of mercury in fish or chlorine we add to flour to make white bread or bromine another pool cleaner.
Bleach which was heavily used in food until recently.
Even still pool chems are not cheap why not just use the correct stuff? Every country the world has access to ag fertilizer.
He'll even make your own using composted food scraps and urine.
I know it's trivial considering heavy metals and stuff but I don't wanna eat the stuffed used as weapons in ww1.
Can you imagine watching your best friends face melting from chlorine then find out it's in every "white" food you eat.
Plus I maybe wrong as it happens from time to time but I'd would assume that even if it will work that's it's different from the minute amount the plant may actually use.
Now I need a reminder why it's advised not to use tap water? Seems the more I read about a plants needs I'm paying extra for water ro come winter
calmag when its in my tap water with everyone micro nute I add to my ro water already.
I'm starting to think not using tap water is bro science. I always figured the chlorine is why your not supposed to use tap water.