The best type of chlorine in an emergency is HTH as this normally contains 50 to 70% chlorine.
The amount of chlorine needed will depend on the volume of water in the well. Add 1 litre of 0.2% chlorine solutions for every 100 litres of water in the well. Stir the water in the well thoroughly with a long pole and then allow the water to stand for at least 30 minutes
Third level