Re: Do I have algae now titled ... GREY MONSTER SLIME MYSTER
The slippery walls are normally a sign of biofilm. Once they get established, they are chlorine-resistant and even shocking may not get rid of them if they get thick enough. However, if one is maintaining the proper Free Chlorine (FC) level relative to the Cyanuric Acid (CYA) level, then biofilms don't get established in the first place or are kept to very thin minimum where chlorine keeps them in check and brushing will dislodge them.
You wrote that you will happily give up the pucks too when they run out, but you also wrote that your current CYA reading was 80 ppm so I'm confused. For every 10 ppm FC added by Trichlor, it also increases CYA by 6 ppm so with a 2 ppm FC per day chlorine usage the CYA would increase by over 35 ppm PER MONTH if there were no water dilution. Are you still using Trichlor pucks?
I would bet that you previously had low FC/CYA ratios and perhaps even algae blooms with zero FC (which is why you may have started to use algaecide in the past) and that biofilms got established early on the past 3 years. You probably never got rid of them so when you stopped using algaecide, they grew faster and the higher FC/CYA wasn't enough to get rid of them. This is somewhat like a new spa situation or what 4JawChuck described in his pool (though in his case, prolonged shocking got rid of it). If you completely remove the biofilm, which the Aquafinesse (and prolonging the shocking) seems to be doing for you, then it shouldn't come back if you maintain the appropriate FC/CYA ratio.
You might check behind light niches, under ladders, etc. just to make sure this stuff isn't lurking in those areas as well. Prevention is far easier then the cure and for established biofilms that is most certainly the case.