I have been using HDC1 filters in my humidifier for years. It is the only recommended filter for the humidifier and I have tried other brands. They just don't soak up enough water and evaporate it. The HDC1 filters soak up almost 2 gallons a day at low speed setting. The other brands won't soak up this much in a week.
Reply from Filters Fast
Hi John,
Thank you so much for taking the time to give your feedback. Your input means a lot to us, and we really appreciate your business. Your feedback is valuable to us, and we will continue to work hard to earn your trust and loyalty. -The Filters Fast Team