Clear instructions for use. The patio looks almost like new (its 30 years old) although to be fair some of the slabs are only 3 years old. Blackspot gets to work immediately so the work can be done in just a few hours (it has to be left on before being washed off) depending on the size of the patio. Wear old clothes because any splashes will stain. There is quite a strong 'chlorine' smell for a while. This is why I gave it 4 stars not 5 and has nothing to do with its effectiveness.

This stuff is amazing. I had totally written off our patio and its large so it looked like a very expensive project. The stones had been totally neglected by the previous owner. After a really good power jet, we applied the product and it was incredible! I know apply yearly and the stone looks like new!

Timely especially welcomed for the work men as they had a tight time line. Thank you

Slabs look good as new after the winter

I have not yet tried the second batch sent to me foc, but am very grateful for that gesture and believe with another application the product will be effective.

I have been using your Black Spot remover for several years now we have considerable amount of York stone and one treatment a year keep it perfect Thankyou

This product works very well but is extortionately expensive at ca £20/litre. I did some research and the active agent is sodium hypochlorite. I bought some 15% sodium hypochlotite for £3/litre and it works just as well, maybe better. My suspicion is that this company are putting a huge mark up on a product which is essentially sodium hypochlorite

This product is already known to us. We are repeat purchasers. Sadly as we have large areas to treat we find coverage expensive as OAPs.

I used Black Spot Removal on a patio laid in 2016 using Indian sandstone. It began to work immediately and lifted the black spots off in no time. Rinsing the morning after my patio now looks like it did when it was first laid, and I'm really pleased with the result.

It did the job - albeit a tad expensive!

This did work but took many applications ( 7 in some places). We tried both the products for artificial stone and real stone thinking perhaps we hadn’t got the correct one. It does look much better but we couldn’t afford another one to finish the job.

Excellent product - recommend by a friend. Wow what a difference this makes. The paths look just like new.

Black Spot's product really does remove black spot better than any other product I've used.

I made two applications not in the same place. The first I pressure washed after the application . The second application due to lack of time didn’t pressure wash and it was cleaned naturally. Will certainly do another application this autumn.

I bought black spot restorer which I have used previously and it works.

I have a travertine patio and was so hopeful about this product after reading all the positive reviews. I followed the directions exactly. After 5 coats (and pooling coats) and waiting the 2 hours in between, it lightened the area but no way did it return the patio stone back to it's original color. Bleach works just as effectively and doesn't cost $50. DON'T waste your time if you have travertine as it doesn't work well.

This product achieved excellent results for minimal effort. I will definitely buy again.

Quick delivery. Pretty good results.

Product delivered very quickly, easy to apply and removed all but the most stubborn stains

Works extremely well. The only reason it’s not five stars is because of its high cost. But all in all it’s worthwhile to get a patio looking like new.