mold, mildew, fungus?

[ghouchu]

i have twice encountered a green growth on cement walks that would flat not come off. the first time i used undiluted, fresh liquid chlorine--12.5%--with 15 minutes of dwell time and a 15 degree nozzle at point blank range. the next time, i kept it drenched in fresh bleach--6%--for a full 1/2 hour of dwell and then used the turbo on it. no luck either time. both customers were understanding, but i wasn't satisfied.

any idea what it could be? how to get rid of it?

thanks

richard

 

[Mike Hughes]

I'm not sure what it is that you are encountering.......but if the customer is happy........that is most important. Remember, you don't want to go crazy on that concrete.....could cause some damage to it.

Good luck.

 

[Harold Brantley]

Richard, do you think there is a sealer on top of the green mildew? If you use 12% chlorine and get no reaction, I would suspect there is a barrier preventing the chlorine from getting to the mildew. If so, you may need a stripper to remove the barrier first, then use the chlorine. Good luck and let us know what you find out.

 

[ghouchu]

harold(or is it hal?)

now that you mention it, there probably was sealant on the first one. there was definitely no sealer in the second incident, but i wonder if something--either spilled on it or occurring in nature--was acting as a sealant. i was tempted to put a little muriatic acid on it--diluted, with maybe 5 to 10 seconds dwell time-- to see what would happen. what do you think?

richard

 

[Larry L.]

I would have done tried it,,,its another "tool" in our trade that has its name in the line up.

 

[gull maint>]

ghouchu

I know exactly what you're talking about.If it is low Is it grass stains from a weed wacker(stained in the surface)?Sometimes it's another plant.It's a green green(you know what I mean if you've seen it).

I'm puzzled also but I don't know any mold, mildew, etc that could stay green with 12%chlorine. I've tried that too.If it was mildew probably would have turned reddish with the chlorine.

If anyone else knows please speak up. Is it something that occurs in the concrete itself?that's the only place I've seen it too, mostly painted concrete.

I can't get it off either btw

 

[ghouchu]

i know what you're talking about on the weed whacker stains and this weren't that. it's the green green vegitation of some sort that you've obviously encountered, too. mine weren't on painted concrete though. in each instance, a little has come off (perhaps the most recent growth?) but the rest might as well have been titanium--nothing more would come off after the first pass. also, it's clearly not a stain from some extraneous source but rather something that was growing(or had grown) on that spot. surely someone out there can enlighten us.

btw, thanks for confirming that i wasn't just having a flashback or trippin' out, that there really is such a substance as i described.

richard

 

[envirobright]

Thompsons or the like

Thompsons or allpurpose cheap sealers with parafin waxes they do the same thing on wood where you can't get to a green stain. Sodium Hydroxide, that you will find in wood deck stain strippers should disolve it. Good Luck Jeremy

 

[jschessler]

mildew

If it does not come out and the customer wants it out, try sprayer with murratic acid or brush , let sit for 35 seconds and pass the surface cleaner over it and it will come out . Use only as a last resort meaning if customer wants it and you have no other options, don't let the water hit the grass and pick up the water and dispose in sanitary sewer.

 

[ghouchu]

thanks fellows.

richard

 

[Richard R.]

ghouchu,

I'm curious.
Was this green stuff in different size spots, appearing like some type of fungus with a olive green color?
Did it look like it was beginning to clean up and re-appeared after the driveway started to dry?
Was there patches of it in different place on the concrete, but not covering the entire concrete?

Richard R.

 

[ghouchu]

richard r.,

yes, it was in patches, as opposed to covering the entire area of cement. there was an olive tinge to it but it was really a deeper, darker green. it wasn't a case of coming back after it looked clean--it just stayed there. the only way to get it up was to blast away the concrete to which it adhered. i used a turbo on it, after soaking it for 20 to 30 minutes with pure (6%), fresh bleach, and loke i say, the turbo did nothing until it was close enough and sustained enough to start taking up pavement. does this ring any bells with you?

thanks

richard w.

 

[Richard R.]

Richard W.
As a matter of fact I have. I've run across it 2 or 3 times including on stone walk ways. If it is the same thing I'm thinking about, this is some very paculiar and essentric stuff. I don't know what it is, but you sound as if you took care of it the same way I had too.
There is a couple of things I would suggest for you in the future.
First off, work on it as much as you can until you feel it's time to let up, then let the concrete dry. Providing it is not in an open area where it is easily seen, Come back after it dries and then apply the 12.5% or the ultra clorox scented or ultra advantage, which has the sodium hydroxide in it. This gives you a straight concentration of your chemical which believe it or not, works a fraction better. Sometimes a fraction better is all it takes. If it works your ok. If it shows only a little change, you may have to spray it and let it set overnight to get the results on a test area. This is what I have had to do on the stone work because of the stones being so soft. Also put some spray easy off oven cleaner and some spray Barrymans B-12 from your Auto store in your chemical arsenol for emergencies. Sometimes you need things like this when there is simply nothing else that will work. Just remember there is no limit to the types of things you can try for this stuff. Since I have an imagination, a 3500 psi washer, a great turbo nozzle and an enormous amount of chemicals to choose from, there are not to many things I can't whip. Sometimes it just takes an incredible amount of time to beat it and that can cost you a lot of money if your on a submitted hourly bases. I just recently bought a wet sand blaster for about half the price everyone else is paying for it and it is super cool. It's a little dangerous but fun.
Please let me know if you ever have anymore problems with something unique.
Please forgive me for saying so, but I'm glad it was you that had the problem and not me. It makes me nervous every time I'm challenged with a new problem like that.
I am really sorry I didn't catch your post earlier enough to help.

Happy Thanks Giving to You and Your Family.
Richard R.

 

[ghouchu]

thanks for your thoughts. i was using clorox advantage--the only liquid chlorine i had was several months old and in the back of my pickup most of that time so it had weakened considerably. i'd be too worried about creating a new and more obvious stain or discoloration to leave a chemical on overnight. i will add the ones you mention to my arsonal, though.

thanks again

richard