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As a rule of thumb, if you can taste the chlorine it is a slightly stronger solution than it needs to be.
https://wedc.lboro.ac.uk/WHO_Technical_Notes_for_Emergencies/5%20-%20Emergency%20treatment%20of%20drinking%20water.pdf
Strictly speaking depends on turbidity and pH levels, but buying chlorine tablets and following their guidance will be close
https://www.butylproducts.co.uk/Products-Services/AidEquipment/Purification/WaterPurificationProducts/
Alternatively Merlin Sierra Leone used a domestic ceramic candle filter
Regards,
Ian