I've just been diagnosed with a ubiquitous pulmonary bacteria called MAC commonly found in tap water and that requires a 0.2 micron filter. It's smaller than other bacteria and treatment is long and difficult. Reinfection is common.
I want to obviously avoid reinfection if I clear it which requires me to reduce exposure as much as possible. I live alone on a 9th floor condo with basement central boilers so an external whole house water filtration system is out-- Ultra Violet and RO systems are not ideal either. For the bath shower, there are hospital grade 0.2 micron showerhead filters. Cold water needs in kitchen and bathroom can happen with an ultrafiltration system filtering down to 0.2.
The dilemma is that it survives dishwashing cycles because the water doesn't get hot enough and, therefore, dishwasher contents not bacteria-free even after the wash. So my thought is to filter my kitchen cold water line w/ ultrafiltration. That comes out bacteria-free. Can I feed that filtered water into an under-counter, tankless water heater that can then feed the dishwasher? The tankless version appeals to me as an added safety to prevent colonization should any slip through. Thoughts?