high desert fun fact: putting tap water in your humidifiers can foul your indoor AQI/PM2.5

I couldn't figure out why my indoor aqi sensor was consistently showing an unhealthy indoor air reading of around 70 during the winter, even with my indoor air purifiers running on low. A quick internet search revealed that using tap water in my humidifiers can increase pm2.5 and aqi to unhealthy levels due to mineral dust/white dust being evaporated into the air by the humidifiers.

I turned off the humidifiers, and the indoor aqi dropped to 8 within an hour.

I still need the humidifiers to keep my house's humidity tolerable. Potential solutions include using distilled water, demineralized water, or water run through a reverse osmosis filter. I'm a renter (no reverse osmosis system) and I don't want to drive to the store to buy water to feed my humidifiers (no distilled), and (edit) chatgpt estimates the cost of annual zerowater filters for feeding the humidifiers to be $500-$1,000, so now that's out too.

So, it looks like I'll be acquiring some wicking humidifiers instead.

(Edit: As others have pointed out, it's helpful to know that this applies only to vaporizing/atomizing humidifiers. This does not apply to wicking humidifiers, which is why these will likely be the solution for me.)