Product review (1 stars): so it's not like it goes days without use
These filters are awful. We used the starry night humidifiers for our two daughters every night. Because of that, we regularly add and clean out the water and every week I flip the filter. I went to flip the filter this week and mold is growing on the filter. We have not even been using this for a month yet, and we flip the filter and add fresh water every day. This gets used daily, so it's not like it goes days without use. I'm disappointed that there us obviously very little quality control with this product and it makes me sick to think mold has been going into my kids bedroom. I will not be purchasing these again, and may I suggest you look elsewhere too.