Dave, I have absolutely followed it to a tee, done every step including multiple brushing daily, checking 4-5 times and very regularly topping up FC. The water is looking really good.
But, I can definitely see that since starting the SLAM areas of the pool are starting to get worse. Ie where the marblesheen is worn I can see it getting less and new areas have broken through (I'll try to take pics). I knew all the weak areas like the back of my hand before starting to SLAM so I can definitely see the change. When I say the surface is worn it's hard to explain in words, I'll take some pics and post them tomorrow so you can see what I mean. The closest way to describe it would be as if the surface is almost dissolving in parts (this is before the slam), where a small mound forms and now I can see more of the black concrete / bottom layer coming through. Several marks like this have worsened since I started SLAMing, so if not the high chlorine what would coincidentally cause it?
In any case I'll measure the FC tomorrow morning and see what the OCLT comes out at, it may well be 1ppm or less. All the algae has gone, I just have tended to see this very slight black dust when brushing the areas it was previous at.
But no question it has helped & the pool is looking great. Test will be if that former algae starts reappearing in patches, hopefully not.
Have these two pics - this is on a wall, prob one of the worst wall marks & is worse since starting the SLAM.
Then see this one at the bottom of the pic? That brownish looking mark isn't algae, it's the surface underneath the marblesheen coating starting to show through. There are a few marks like this around the pool, and I do believe several have gotten worse since SLAMing.