Concrete stains on monoblock

[MoonMan2]

I have, what I believe to be concrete 'stains' on my monoblock.

I tried to scrub away the stain with cold water and then hot, this was the result:

Anyone help?

 

[HERTS P&D]

Jet washer.

Andy

 

[MoonMan2]

What pressure would I need?

Checked an amazon, there are a wide range of these devices available at varying prices.

 

[HERTS P&D]

Try and borrow one from a neighbour first. Or work out your budget and go for a Karcher model.

Andy

 

[MoonMan2]

Would this be powerful enough?

https://www.amazon.co.uk/dp/B01NGU8Z32/ref=psdc_114633031_t2_B0829J32VH

 

[JohnD]

It will weather away. Have another look in a year or so.

 

[HERTS P&D]

Would this be powerful enough?

https://www.amazon.co.uk/dp/B01NGU8Z32/ref=psdc_114633031_t2_B0829J32VH

Yes, that would work.

Andy

 

[MoonMan2]

It will weather away. Have another look in a year or so.

Are you sure, I mean I tried to scrub it off with a brush with stiff bristles?

 

[JohnD]

It's probably mineral salts that dissolved in water, rising to the surface and left behind as the water evaporates off.

trying to clean off with water is fairly unsuccessul. if the salts redissolve, they soak back in. The extra water, when it dries out, evaporates off the surface and leaves more salts behind.

It is similar to limescale. Sand and cement both contain a variety of minerals.

 

[lonner]

Cement acid cleaner,

 

[MoonMan2]

Which will give best result, cement acid cleaner or jet washing?

 

[lonner]

Which will give best result, cement acid cleaner or jet washing?

Cement acid