Hello, I use a Lifestraw just to add a little extra precaution to what goes in. I had my water tested for MAC and it was negative. I still use the straw. As far as the dry salt inhaler, I never felt that inhaling cold, wet air into my lungs was a good idea so I switched to dry salt inhaler (Nevelers on Amazon). Purely anecdotal.

Hi Mokie, and welcome to Mayo Connect. I notice in another post you mention you are new to our site and our support group. Mayo Connect is a place for patients and caregivers, who are not medical professional, to share our information and experiences. We do not replace doctors and other providers, but many times our shared experiences lead you to ask better questions of your team, and find the best treatments for you.
You might be interested to read about some of our experiences to get a sense about how wide the range of levels of illness, effective treatments and personal efforts to "tame the beast" that is MAC and Bronchiectasis. Click here for a recent discussion: https://connect.mayoclinic.org/discussion/macntm-is-different-for-everyone-treatment-might-be-different-too/

Here is what MOST of us have in common:
We have Bronchiectasis or another chronic lung condition (like asthma or COPD)
We have or had another lung infection like MAC (also referred to as NTM or MAI), pseudomonas or aspergillus
We do airway clearance - with a device, a nebulizer, a concussion vest or breathing techniques to keep mucus out of our lungs as much as possible and avoid infections
We take precautions to avoid exposure to NTM and other infectious agents because our lungs are vulnerable.

Here is how we are DIFFERENT:
We may or may not take antibiotics to treat NTM. There are as many reasons as there are people.
How we do our airway clearance and how often
What other actions we take to keep the mucus thin and moving in our lungs - nebulized 7% saline, medications, supplements, exercise...
What precautions we take to avoid exposure

There is far too much information to repeat here, but I will answer the questions about the dry salt inhaler and LifeStraw.
There is quite a bit of evidence that salt suppresses the growth of NTM. National Jewish Health and other experts recommend using 7% saline solution in a nebulizer to introduce it into the lungs, where it serves to make an inhospitable environment and to thin mucus so it can be more easily expelled. Whether a dry salt inhaler also known as "halotherapy" is as effective is just now being studied. Here is a paper citing several studies, if you like heavy reading.
https://pubmed.ncbi.nlm.nih.gov/32827399/
NTM can be in drinking water. This can be problematic for people with GERD (reflux) because some of that water may find its way to the lungs. Regular water treatment and filters are not sufficient to remove mycobacterium, so people choose to use a filter like LifeStraw to further filter their water. Others boil their water, or drink bottled spring water.

The more you read, the more questions you may have - there is so much to learn!
Sue