Terrible results
These things do take some contaminants out , but they leave a very disgusting ring around the interior of my hot tub and pool.  And the ring is so bad that I had to completely drain them because it smeared with its oily residue.  The item even fell apart and left bits all in the water.  The directions were followed correctly but the residue and life of the product is NASTY . I don't recommend this product to anyone.
Rating: 1 stars