Common bleach would work just fine.
(( Proportions, please.
Here is a good link. You can search around the site for other information on water treatment. Bleach has a very limited shelf life (year). When you store pool shock it is advisable to store them in canning jars with plastic lids (Walmart) with a wax seal. The outgassing is very corrosive.
Letter Re: Disinfecting Your Drinking Water
This is a good start.