I was conned into getting a 18ft AGP by my family. All went well for a week or so and then one day I noticed a slight film on the pool surfaces. I found TFP and immediately started studying. I realized chlorine tablets were most likely useless and got some liquid chlorine while I waited for my Taylor 2006 to come in. Vacuumed and added chlorine hoping to avoid needing to slam. Once I got my kit in I brought my CYA up and learned how much liquid chlorine I needed to add to my pool . I did the overnight loss test and passed no problem.(the film went away within 12 hours of my first liquid bleach application) I feel I am on my way to a trouble free pool and am very grateful to this site and all its contributors!