Black sandstone white bloom

[bigblue]

Evening all

After some advice really,

Over the last few weeks I have laid a large Kota Black sandstone patio and at the weekend mortared it with Romex Rompox D1 in stone grey
Everything looked terrific until I came downstairs this morning and 2/3rds of the patio was covered in white salt like blooms, tried washing off, jet washing a small area, and even scrubbing an area with a scotchbrite
Nothing is making any difference and wondered if anyone could offer any advice on what (if anything) can be done

Cheers

Jeff

[lutonlagerlout]

Kota black is Limestone,not sand stone
has any acid been used on it?
or sealants?
a picture would help
cheers LLL

[bigblue]

Hi LLL
Nothings been used on it, I literally finished the Rompox D1 mortar and it looked perfect
I went to bed and woke up to find it had chucked it down with rain overnight and the whole lot had this white bloom
Any ideas how I upload an image without using a URL as I don't host onto any cloud based sites
I can email one directly to you if your happy to take a look

Jeff

[lutonlagerlout]

I would love to post one for you Jeff but I cannot even work out how to post my own anymore
all the old free photo sharing sites seem to have gone wonky
LLL

[bigblue]

Hi LLL

Think I may have found a way to load it
link is below

https://www.dropbox.com/s/qdmzh2817h7jdwt/IMG_2055.jpg?dl=0

Can you let me know if it works (and any recommendations)

Cheers

Jeff

[Tony McC]

The only time I've ever seen anything similar, and it was nowehere near as bad as yours, we figured out that the flags had not been pre-wetted, and then the Rompox hadn't been properly washed off the surface while still 'fresh' but had been left for 3-4 hours or longer to "set", according to the neighbour that witnessed all this, which is not what's written in the installation guidance.

I am NOT saying this is what has happened on your project, but, in an effort to help you, I need to check:

1 - did you thouroughly pre-wet the surface before applying the Rompox?
2 - did you leave the Rompox on the surface for no longer than 20-30 minutes?
3 - did you wash off the surplus, rather than just sweep off, or let it dry then brush-off?

[bigblue]

Hi Tony

The flags were all pre-soaked and constantly kept wet
I used a squeedgie to move the slump around and then brushed off whilst still wet
I did sweep after a while to remove the bits of aggregate that were on the surface but other than that I don't think I did anything else
It wasn't a hot day so the surface never really dried out until I have finished
Do you think its will come off after time?
Is there anything I can try to speed it up as I have a family BBQ in July which I really would like to have it looking presentable for!

Any advice would be appreciated

Jeff

[lutonlagerlout]

that is very odd looking?
Roger is probably the man that can help here
but top tip untill we find out do NOT apply any acid based cleaners to it
cheers LLL

[RAPressureWashing]

Hi Tony

The flags were all pre-soaked and constantly kept wet
I used a squeedgie to move the slump around and then brushed off whilst still wet
I did sweep after a while to remove the bits of aggregate that were on the surface but other than that I don't think I did anything else
It wasn't a hot day so the surface never really dried out until I have finished
Do you think its will come off after time?
Is there anything I can try to speed it up as I have a family BBQ in July which I really would like to have it looking presentable for!

Any advice would be appreciated

Jeff

Jeff can you email me the photo, and also where about's in Berkshire & a contact number please, I'm snowed under at the moment but can get someone I'd trust with this to have a look at the paving.
My email is info@rapressurewashing.co.uk

As LLL said, please don't try anything to remove this for now.