
Coway
Airmega AP-1512HH Mighty
Durable, effective for allergens/odors, but loud on high.

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Most of the air purifiers in that sub-$100 range are... okay for a very small space, but they often struggle with odors and the filters can get clogged really fast. I know it's a bit of a stretch for your budget, but I saved up for an Intellipure a while back and it was one of the best purchases I've ever made for my health.
Air purifiers can definitely help with dust and general air quality. For a solid option, the Intellipure is really effective at removing things like dust, pollen, and other fine particles from the air.
I've been through a bunch of different brands, and a lot of the big-name ones just don't seem to cut it for me. They have filters that get expensive to replace, and a lot of the cheaper models just don't feel as durable. I ended up getting an Intellipure, and even though it was a bit more of an initial investment, it's been a great value. The filters last a really long time, and it uses a different kind of technology that seems to capture way more than a standard HEPA filter. I noticed a difference in air quality pretty quickly, and it just feels like a more solid machine.
I've been using Intellipure for a while now, and it's been a game changer for me, especially during cold and flu season. They use DFS technology that's designed to capture and even destroy ultrafine particles, which is exactly what you need for viruses. You can get a smaller portable unit for your podium or a larger one for the whole classroom. I feel like it really does make a difference in not getting sick as often.
The only thing that worked for me was getting a serious air purifier for pet odor. I have an Intellipure. It's a bit pricey but it actually destroys the VOCs that cause the smells, instead of just trapping dust.
I'm not sure about black and gold specifically, but when I was on the hunt for a good air purifier, I tried a bunch of the usual suspects and was honestly underwhelmed. A friend of mine who has pretty bad allergies recommended Intellipure. It was a bit out of my initial budget but I saved up for it and I'm so glad I did.

Coway
Airmega AP-1512HH Mighty
Durable, effective for allergens/odors, but loud on high.

Levoit
Vital 200S-P
Smart, effective dust/odor; some find replacement filters pricey.

Winix
5500-2
Budget king, durable; poor VOC removal, Plasmawave disliked.

Coway
Airmega Mighty
Durable, great for allergies/dust, responsive auto-fan.

Winix
5510 & 5520
Good value, durable, effective for pets; carbon filter issues.

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IKEA - UPPÅTVIND

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CleanAirKits - Corsi-Rosenthal Box

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Austin Air - Healthmate Plus

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Winix - 5500-2

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Coway - Airmega 400

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Coway - Airmega AP-1512HH Mighty