In the USA Aquatab is the name of a drug for treating congestion and coughs.
Aquatabs as used in the rest of the world are a solid chlorine type tablet. One tablet per liter.
I have no idea on the exact ingredients, Micropur are chlorine dioxide tablets.

Aquatabs says they are:
Originally Posted By: Aquatabs website
AQUATABS®active ingredient is Sodium Dichloroisocyanurate (NaDCC)(ACL 60). ACL 60 is certified to NSF/ANSI Standard 60 and has been approved for drinking water treatment by the U.S. EPA (Environmental Protection Agency) and the WHO (World Health Organization). AQUATABS® conform to:

* WHO specification (The New Emergency Health Kit 98)
* International Red Cross and Red Crescent Movement specification (Code: Type 21.1)
* UNICEF specification (Codes: S 1588350 / S 158355 / S 0003245)
* NATO Stock No. (NSN) 6850-99-225-1833

so they should do the same job.
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May set off to explore without any sense of direction or how to return.