Horti-Control Dust Shroom HEPAHorti dust control shroom HEPA are a foam HEPA filter that helps remove unwanted pollutants, pests, dust, mold, trap 99. 9 % bacteria, 0. 1 microns, and even bacteria from indoor gardens and keep your space kid friendly. It also helps trap 99. 9 % bacteria particles, 0. 1 microns, and pollen at bay. Pollution prevention with Foam and UNI filter: Foam filters are mostly used to prevent pollution from air cooled reflectors, inline fans, mold, etc.