RogerT wrote:
Having spent a couple of days getting wet whilst trying to clean the
summer's accumulation of green/black algae/gunge/dirt from the
concrete patio slabs with a pressure hose, I'm sure there must be an
easier way.

Apart from paying someone else to do it, is there either an easier or
more permanent way to achieve the "new whiteish-grey slab" look?

For loose dirt a stiff yard brush and some elbow grease.

For algae we've used Algon over the last year. We find we need to do it
every 6 months - (limited) details here http://www.algonorganics.co.uk/ -
can be picked up in garden centres.

It's about £5.99 for 5 litres, you dilute it in water and spray it on and
leave it. Has worked well on our north facing slabbed back garden.

It's 'organic' - I think it smells quite vinegary. I was out on Sunday
giving it's autumn spray, and they've cleaned up well, but more importantly
aren't slippy any more.

It's not a permanent solution, but nothing is - if you've got a darkish damp
area you're going to get algae.

--
NK
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