Pool Blok PB-12 by US Pumice, Pumice Stone for Cleaning of Pools, Tiles, Will Remove Lime, Rust, Stains from Pool Tiles Grout, 5.75x2.87x2.87 (1)

First time to use and was easy and great job! Much better than the liquid calcium build up pool cleaners!

Product works well. It does wear out a little faster than I anticipated, but it also does get the cleaning done.

If using to clean pool tile, you will definitely need more than one. The product wears down very quickly. Would not buy again due to cost and need for many of these to affectively clean

It's difficult to write a view for something that literally disintegrates in your hands when you use it, but that's what these things are supposed to do. That being said, it's abrasive qualities are good enough to remove some lime scale and calcium, but soft enough not to damage any nice porcelain. I use these on the tiles in the pool about once a season. One of these is enough to do the whole pool once so the price is a little pricey considering I can get some other brands cheaper with more product. However, I find that the overall softness and cleaning power of this one is pretty good for my tiles in my pool.

I was skeptical but OMG it’s wonderful. We just had our pool redone 3 years ago and I was devastated when I saw how much calcium gross grey build up was around my new tile. When this came in, I immediately went out and got to work. It buffs off the calcium beautifully and didn’t scratch my tile. It takes a little elbow grease but not as much as you think. I’m about to order another stone because I was only able to do 1/2 my pool which is a medium sized kidney bean shape. I never take pics or write reviews but I for this I knew I needed to. I was also able to use it on my gunite pool steps. It got this red stain off as well. 100% recommend this product. I uploaded 3 pics to show before, the process and then the final.