To disinfect a system, a basic rule of thumb to shock disinfect with
chlorine indicates we need to bring the chlorine concentration to about
50 ppm. Clorox contains 5.25% chlorine, so do a bit of math.
For a 100 gallon tank, multiply 100gal. x 50 ppm -> 100 X (50/1,000,000)
= .005 gal.
So we need to add .005 gal of chlorine.
Household bleach (Clorox) is typically 5.25% chlorine, so 1 gallon of
Clorox = 0.0525 gallon of chlorine.
For our 100 gallon system, .005gal/0.0525= 0.09524 gallons of bleach.
That converts to ~ 12 oz. So, 1-1/2 cup of Clorox is needed to create a
concentration of 50 ppm in 100 gal.
Contact time for a 50 ppm concentration is 6 hrs. For 24 hrs. contact
time, the concentration can be reduced to 10 ppm, or for 100 gal. tank,
a dose of 4 oz. Clorox.
These are
conservative concentrations, meaning they're
already
overkill. More isn't necessarily better - enough is enough! Higher
concentrations won't make the bugs more dead, they'll only complicate
the flushing and rinsing of the system. Once the tank is disinfected, it
should be flushed & rinsed with clean water, then it's ready to use. A
carbon taste & odor filter installed in the main supply line downstream
of the pump will remove any remaining chlorine taste, and help with
keeping the water fresh tasting and enable you to dispense with the
plastic bottles. Once the tank is disinfected, there's no need to
routinely disinfect it other than perhaps an annual preventive shock.
So
keeping tanks suitable for domestic use simply involves filling
them with clean water and
using it!
Hope that helps! Drink tank water!