so much, just like a sponge. If it is still sticking to the carpet, there is more soap from previous cleanings still in the carpet, and a second application should remove it.  The compound is wet with a solution of primarily water with some detergent and solvent in it. The amount of detergent in the Host is miniscule compared to what is injected in extraction cleaning. If you allow unused Host to dry, it will not stick even to itself, so it has to be sticking to residue still in the carpet.  A 6lb box will cover 500 sq ft of average soiled carpet.  When people opt to rent a Sanitaire with the Host, I send a 3 pack of bags with it, and tell them to change the bag before picking up the host. Three F&G bags full of Host is pretty much the volume of a 6 lb box. If you pick up that much, you pretty much got it all. Allergies to Host are rare. It is used in health care facilities.

Thanks for the pics.  I had no idea the Orbiter would work so well with the Host.

for 'average' soil is 500 for 6 lb, and, obviously 1000 for 12 lb. If the carpets are really dirty, misting with the pre-spray and brushing before applying the Host will help. Once the carpet is clean, maintaining is easy.

are likely urine molecules that have actually inserted themselves in between the molecules of dye in the carpet. Both are acidic. The molecules of uric acid are smaller than the molecules of dye.  It would be interesting to try the 'dye transformers' that actually break off an oxygen molecule from the dye to render it invisible in the visible light spectrum. I wonder if it would have the same effect in the ultra violet light spectrum.  Lindhaus makes a very effective chemical of this type.