Are you talking about those petri dishes you put out? I have heard from a trusted mold expert that they just always show up positive. I don't know that I trust that, but the problem is that every house actually has mold, and in many places, and who knows what's actually contributing to the problems. Are massive air purifiers enough to mitigate the issues? Can you just tackle the surface molds? Maybe these questions are answered in the mold course, I need to take it asap.

> Are massive air purifiers enough to mitigate the issues?

As far as I know, air purifiers do not filter mold related particles in the air to any useful amount.

Depends on the model. HEPA filters can filter mold particles.

The petri dishes are for ID and yeah theyll be positive. Real air quality spore measures require a filter disk and vacuum. Then you need to compare counts inside vs outside. There will always be some level, which is why it's important to compare with ambient outdoor levels. Some say you even need multiple samples at varying weather conditions. Then types are important too.

It's not possible to reliably test if the air has harmful amounts/species of mold or not. The air quality tests contaminate very easily and even when they don't contaminate, there is a lot of uncertainty with the results, and given any particular results, different people will opine different interpretations of them...

The filter/vacuum testing is pretty good. You do need a baseline to compare it to, which is often the exterior spore count. Yes, the recommended actions can be all over the place.