Best Paving Slab Cleaner?

20 Dec 2012
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United Kingdom
Can anyone recommend a good paving slab cleaner for removing algae etc?

I don't have a Pressure Washer.

The ones that seem to be good on the internet are:

Wet and Forget

Spear & Jackson Spray and Leave

Patio Magic Patio Cleaner

Does anyone have any recommendations? Thanks
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I used near neat Milton to good effect. The best moss remover ever was a pile of earth which starved it of sunlight.

A bottle of bleach in a bucket of water and scrub it with a yard brush. A rectangular bucket that the brush will fit into works best.
I have used Patio Magic Patio Cleaner to kill moss and it works well. However that and Wet and Forget (which I have not used) both use benzalkonium chloride (also called alkyl dimethyl benzyl ammonium chloride) as the active ingredient.

I suspect that Spear & Jackson Spray and Leave will be the same or similar.

W&F and PM are c. 8-10% and you dilute them down to c. 1-2% for use. I bought 5L of 50% benzalkonium chloride as that is a more cost effective way of buying it.

I use it on moss, not algae, and it certainly kills the moss but it does not remove it. The moss is still there but shrunken & brown.
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Spear & Jackson Spray and Leave works great!

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