Which grout haze remover is best? First one didn't work.

[Bob H.]

I recently installed some black ceramic tile with white grout. I realize now that the high contrast between the tile and grout makes any haze particularly noticeable.

The tile surface is smooth, with a silky texture. When installing the grout, I had little trouble scraping it off with a float, leaving nice straight joint lines. I did notice, though, that a light gray haze was forming. After scrubbing this without much success, I decided to try a haze remover.

I installed the grout over two days. The following day I tried Miracle Sealants Heavy-Duty Acidic Cleaner. I diluted it according to the instructions and even tried it full strength in a few spots, being careful not to get it on the grout joints.

The effect was barely noticeable. There still is a light haze on a lot of the tile.

The label of the Miracle Sealants product says it contains hydrochloric acid.

Another product, Aqua Mix Cement Grout Haze Remover by Custom Products, contains phosphoric acid, as does Deterdek Cementitious Grout Haze Remover by Fila.

Another option is Aqua Mix Sulfamic Acid Crystals by Custom Products.

I also have seen recommendations for using acetone to remove grout haze.

I want to get this right with one more cleaning, and I don't want to stain or damage the grout in the joints. Which of these products do you recommend, based on experience with them?