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I have update for the UV section.
Maybe your info is based on old studies: you don't need to kill Crypto, it's enough if it is not able to reproduce.

̈I included here part of the public domain document.


Ultraviolet Light Disinfection in the Use of Individual Water Purification Devices

Bacteria, Virus, and Protozoa Inactivation Capability
Microorganism Inactivation Capability
The effectiveness of UV light on microorganism inactivation varies with different types of
microorganisms. Generally, UV light is most effective at inactivating Cryptosporidium and
Giardia, followed by bacteria and then viruses:
Cryptosporidium and Giardia > Bacteria > Viruses
Interestingly, UV resistance appears to follow microorganism size, with the smallest
microorganisms being most resistant. The reason for this may be due to the amount of UV light
absorption per cell. With microorganisms larger than 1 micron, the absorption of UV light by
the cell can be significant, effectively reducing resistance to UV disinfection. Table 2 is a
summary of numerous UV disinfection studies and shows UV doses and corresponding log
inactivation for various microorganisms. The most UV resistant viruses of concern in drinking
water are adenovirus Type 40 and 41. Because viruses are the most resistant to UV disinfection,
dosing is controlled by log inactivation requirements for viruses, not protozoan cysts.
As Table 2 shows, Cryptosporidium and Giardia are very sensitive to inactivation by low
doses of UV light.