You're entitled of course to your opinion, I respectively state that is incorrect, about the sizing.
KDF
Why we don’t use KDF is 55% zinc 45% copper
It adds copper to the water
It must be backwashed within the softener, if it not back washed with enough force it will not fluidize
If so it turns into a sold block and no longer works.
Must be backwashed at 10-12 gallons a minute using a fair amount of wasted water, most softeners don’t have that flow capacity. So it takes about 90 gallon to backwash effectively
The kdf containers are fragile, they can come apart with the softener.
one family has a website with their issues
My Story: Heavy metal test proved that heavy metals contributed to oxidative damage - ToxicWaterSolution.com
It is expensive to replace every 5 years, no way to tell if depleted.
One local place quoted $1095 to replace it.
Not saying it’s a bad product we don’t think it’s as effective or safe as carbon.
Copper is absorbed through your skin. Copper in the shower or bath steam can be absorbed through your lungs.
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