I have four Doberman Pinchers and two Great Danes that roam through my house. I purchased a 1 lb. container of ClenAir Super Gel and put it in my return of my furnace and put my blower on constant operation. In few hours you wouldn’t even know I had any pets at all. ClenAir Gel is truly a great product and I believe in it 100%. I also tell other HVAC contractors about it.