Leaf stain in slabs - how to shift?

[Richard Ivy 14]

Until my super duper 200BAR pw arrives from the US, I have to soldier on with my crummy 120 BAR machine.

I cleaned some cheap looking slabs today for a neighbour, but couldn't get rid of what appears to be, pretty sure of it, stains left behind by leaves. (brown/rusty colours).

I think I have read somewhere on TGS about this, but can't find it.

Has anyone a tip on removing these stains?

Thank you.

[Larry B 55]

Bleach is the common name given to chlorine. The 12% is the concentration of it in water. 12% is almost the stongest you can get, the common Clorox brand bleach is around 5-6%. The chemical compound name is NaHClO3. You can only purchase the 12% from pool suppliers and chem companies.

Oxalic is an acid that you would not want to use to clean a house. Most of your house washes would be to clean mold and mildew and bleach/chlorine is what that is good for. The reason you would want to purchase 12% is when you use an x-jet the mixture will get diluted. If you use common 5-6% bleach/chlorine it will usulaly be too diliuted to do the job efficently and effectivley unless you apply it wiith a pump up sprayer.

[Richard Ivy 14]

So when you buy chlorine it doesn't come any stronger than 12%?

[Larry B 55]

I can get 15% but that is it. It is strong and unstable and the gas can be very hazardous.

[Jarrod 22]

This thread is very informitive! Thanx to all who posted.

Hey Jeff, who's the girl?

[Jeff 232]

This thread is very informitive! Thanx to all who posted.

Hey Jeff, who's the girl?

Jarrod its a bartender, These are pics from Bike week we have 3 every yera in Myrtle Beach its a fun crazy time

[Mike Williamson 198]

Until my super duper 200BAR pw arrives from the US, I have to soldier on with my crummy 120 BAR machine.

I cleaned some cheap looking slabs today for a neighbour, but couldn't get rid of what appears to be, pretty sure of it, stains left behind by leaves. (brown/rusty colours).

I think I have read somewhere on TGS about this, but can't find it.

Has anyone a tip on removing these stains?

Thank you.

I spray sodium hypchlorite (pool chlorine) and that clears it up fast, typically either downstreamed, or a bit stronger in a pump up sprayer.

[Mike Williamson 198]

Sorry I don't understand what this means: 'Need a good Ph+ oxidizer? Try 12% NaHClO3'

Secondly, do you apply oxalic acid dilute in a pump up sprayer?

Thank you.

Nevermind..it's been handled in the thread...I guess I should read the whole thing before responding!!

[StainlessDeal 16]

What is commonly referred to on these BBSes as "chlorine" or "bleach" is a solution of sodium hypochlorite. It is available in various stregths, usually 6%, 10%, 12%, or more rarely, 15% solutions. It is also called "liquid pool shock", and in the States is easily purchased at pool supply houses and chemical suppliers. It is unstable in that the amount of chlorine in the solution decreases rapidly as the solution decays. Keeping it cool and dark helps to mitigate this, but all sodium hypochlorite is decaying and getting weaker, so you have to keep an amount on hand that suits your use.

I can get as much 10.5% solution as I can use a week at a reasonable price, and 12% for a little more per gallon, but my use varies widely so I generally buy a bit more than I have estimated using during the week. At any given time I have 10 to 25 gallons undiluted on hand, so I buy 10.5% and figure my ratios from there. I only buy 12% when I know I will use it all since pretty soon it will be 10% solution anyway.

The oxalic is a great remover of stains that were left by evaporation of mineral-laden water on surfaces. The iron in the irrigation water sprayed daily on the fence in Jeff's pic's being a prime example. And just as an aside, you definately don't want to EVER be sprayed with Oxalic: It can lead to sterility in men.:lgtear:

I hope this answers the basic question you were after.

[StainlessDeal 16]

When I sat down to write that last post, there were like six fewer posts in this thread, I got a quick phone call, but man, what a quick bunch! :lglolly:

[Jarrod 22]

Jarrod its a bartender, These are pics from Bike week we have 3 every yera in Myrtle Beach its a fun crazy time

Oh yea! My brothers went to that last year.

[Jeff 232]

Richard your in the UK do you know if there is liquid chlorine 12.5% sold in your area?

Or in the market do they sell bleach its basically the same thing just weaker

The 12.5% liquid I buy is from pool supply company and a couple times or when I 1st started PWing Ive used bleach from the market it still works you just need more in your house wash mix

What do they have in your area?

Jeff

[Barry M 73]

Hey Jeff or others, I have a driveway to do this spring that has tannin stains and irrigation rust stains, do you think I would have to wash it twice, once with chlorine for the tannin stains and then again with oxalic? If I remember right these two chems are dangerous when mixed.

Also Jeff did I understand you right in an earlier post, you PW the sidewalk with surface cleaner and then apply the oxalic?

Didn't mean to steal your post Richard.

[Mike Williamson 198]

Hey Jeff or others, I have a driveway to do this spring that has tannin stains and irrigation rust stains, do you think I would have to wash it twice, once with chlorine for the tannin stains and then again with oxalic? If I remember right these two chems are dangerous when mixed.

Also Jeff did I understand you right in an earlier post, you PW the sidewalk with surface cleaner and then apply the oxalic?

Didn't mean to steal your post Richard.

Wash it, spray it with chlorine, rinse, apply oxalic. Better to get all the dirt and everything off/out of the concrete before applying the chlorine or oxalic.

[Jeff 232]

Wash it, spray it with chlorine, rinse, apply oxalic. Better to get all the dirt and everything off/out of the concrete before applying the chlorine or oxalic.

Barry just as Mike says, but rinse the bleach off pretty well occasionly if you mix Ox & Bleach on concrete it can leave a little outline of a stain. I ant really explain what it looks like but just rinse the bleach off good

Ox & 12% isnt as bad as Muratic & 12% NEVER mix the 2

[mikew 14]

Great thread everyone! Really good info here.

Mike

[Crownroyal 14]

I wanted to pip up I'm not sure about the leaf stains but make sure your not applying bleach over rust because I remember hearing that bleach will help rust to Adhere to concrete making a chemical bond which is hard to remove. If I’m wrong I’m sorry but I thought I was sure you shouldn’t do that. I think that is why some rust spot you get called to clean won’t come out like normal. The homeowner sprayed bleach on it like ten times and you’re sitting there losing your mind.

[Mike Williamson 198]

I wanted to pip up I'm not sure about the leaf stains but make sure your not applying bleach over rust because I remember hearing that bleach will help rust to Adhere to concrete making a chemical bond which is hard to remove. If I’m wrong I’m sorry but I thought I was sure you shouldn’t do that. I think that is why some rust spot you get called to clean won’t come out like normal. The homeowner sprayed bleach on it like ten times and you’re sitting there losing your mind.

I've never heard this, but chlorine CAN cause rust stains to get worse, if the source of the rust is in the concrete (such as a piece of metal/rebar). I'm sure you've run into a situation where the rust seems to be seeping from a small hole in the concrete?

Some things that appear to be rust stains aren't, and are unaffected by oxalic, like fertilizer stains, or stains caused by battery acid.

[CCPC 26]

Some things that appear to be rust stains aren't, and are unaffected by oxalic, like fertilizer stains, or stains caused by battery acid.

I've always figured that the fertilizer stains were rust stains, at least that's what I've been told in the past as well, that the stains come from the iron and other minerials getting wet and rusting, seeping into the concrete.

If it's not rust, then what?

[Mike Williamson 198]

I've always figured that the fertilizer stains were rust stains, at least that's what I've been told in the past as well, that the stains come from the iron and other minerials getting wet and rusting, seeping into the concrete.

If it's not rust, then what?

No idea! I just know what I've read here and elsewhere, about fertilizer stains not being affected by oxalic.

[paul-uk 500]

ok richard got your pm will be in touch and bring you up to speed with what you want.....one thing for anyone who has not used oxalic,,,it is very dangerous to handle and use ...so do read up on it .....try the search on this bbs.speak soon rich.

[HotShot 34]

WOW...this is a great thread. I just wanted to bump it so that we newbies can find it easier..:)

Thanks guys for all your posts, they will really help me tonight

[Anthony G 14]

Here is the back of a school that I did using 12.5% and the x-jet at a 4-1 ratio. The previous pw'er had tried it cutting to 40-1 which didnt work and I ended up on the job.

If it doesnt insert then try this website address

www.sugartreekennels.com/powerkleen

it is the second photo.

[grizzley 14]

stupid question...

How do you mix it?

12.5% (1 lb power bag) into how much water? Do you add anything with it (Dawn, etc..)?

I invision (1) 1 lb bag mixed with 2 Gallons water and then X-Jet but I really don't know.

[racechaser 64]

It is in liquid form.Just like household bleach only stronger and a different formulation.It's called sodium hypochlorite.

Scott

[A and J POWERWASHING 64]

use bleach i had same problem on sat. and it cleaned it up in about 5 mins w/ low pressure about 800 psi