Patio Black Spot Remover for Natural Stone – Patio Cleaner and Restorer for Indian Sandstone, Limestone, Yorkstone Paving Slabs – Remove Black Lichen, Green Algae and White Fungi – Biodegradable – 2 L

Works well, but you need quite a lot. (I used a 4L bottle for around 15-20sqm and will need another to finish the patio.) Easy application using spray hose - takes about 2 hrs to work before pressure washing. I kept topping up heavily stained parts during this time which were drying out quickly. Will need a second application in places to remove heavy markings. The smell is quite strong but dissipates overnight, and it will bleach your clothes and some grass alongside paths so don’t do it in your nice jeans! I think it’s the same chemical formula as bleach, just a lot stronger. Oh, and as someone else mentioned - remember to remove your shoes to avoid bleaching your carpets and floors !

Exceptionally good at completely removing heavy black/grey stains from Eqyptian limestone, which had defeated pressure washing and scrubbing. Apply and watch the stains lift in real time, no other work required, slabs left looking like new. Must be applied neat, making it expensive for large areas - do a test beforehand to see how much you need and to avoid using too much.

The product is good, just doesn’t go very far. Think 2litres were enough for my patio but had to order another 4 litres. Bit expensive but did restore 95% of my patio back to looking good

Absolutely incredible result. My 17 year old patio was covered in black spots and grime I have pressure washed if every year but that does not remove black spot. After using Black Spot remover it is almost back to how it was after it was laid. It is so easy to apply with amazing results. It is expensive, I need 3 x 4 litres as it is 40 square metres but it was definitely worth the cost.

Brilliant, does exactly what it says it will do. Fast acting and you can see it working straight away, only downside is it doesn’t go far so you may need two packs. Will definitely buy again.

I bought this as it said it was pet friendly and Was a bit sceptical at first but sprayed it on, left for 2 hours then washed off with a jet wash and the slabs are cleaner than they have ever been and all black spots have gone, this is expensive but works very well.

black spots all gone , definitely works, I was amazed how fast it worked ,

Expensive and got the patio slabs nice and clean but didn’t remove the black spots. Not sure it would have been any worse if I’d just jet washed the patio with water.