Re: what cleans pool tile *best ?
PSI washer didn't work on my pool tile.
I didn't try CLR, but did use a sanding stone very carefully. Or you scratch the tile.
My Dad used diluted Muriatic acid on his tile. He wore rubber gloves and floated a plastic bowl with the diluted acid in the pool. Then he painted it on the tile with a paintbrush and washed it off with pool water. I've never tried it, but he said it worked.
Pool tile cleaners blast the tiles with special glass beads and then vacuum them up. I had mine done that wasy and it looked great. Cost about 500.00 though.