Green Algae growing on concrete?

[cdreed06]

This may be elementary but I was wondering what gets the green algae off the floor and concrete walls? I spray it off several times a week and it still comes back. Looks black in some places and green in others. Anybody have any tips? Thanks in advance.

 

[Kevin James]

Straight BLEACH out of the jug.

 

[cdreed06]

Thank you very much.

 

[PaulLovesJamie]

I dilute bleach 2 or 3 :1 and spray it with a cheap garden sprayer. Let it sit for 5 or 10 minutes, then use HP rinse to wash it down.
Once in July is usually enough, but I often do it again in Sept just to get the bay floors really clean for the winter.

 

[MEP001]

I do the same as PaulLovesJamie, but I don't rinse it off. It smells for a few hours so I try to do it late at night.

 

[Earl Weiss]

Bleah works and is inexpensive. There is another product called "wet and forget" and the resutls are supposed to last months, but who knows in a car wash environment.

 

[Kevin James]

Household bleach is only 3 or 5% Sodium hypochlorite, the rest is water. The maintenance guy’s like to use it straight out of the jug in a sprayer. It turns the green algae brown right now, and then they use the high pressure gun to clean of the dead brown stuff. If you don’t clean off the dead algae it will come back pretty fast

 

[cdreed06]

I appreciate the answers, I will use the bleach from a garden sprayer as soon as I can. Thanks everybody!

 

[Rudy]

I spray some algicide used in swimming pools instead of chlorine. It works better. After all, algae loves to grow in chlorinated water doesn't it?

 

[bigleo48]

I just use one of these...

 

[2Biz]

I spray some algicide used in swimming pools instead of chlorine. It works better. After all, algae loves to grow in chlorinated water doesn't it?

What ratio do you dilute with water. Its pretty concentrated....

 

[Rudy]

To be honest....I can't remember how much I diluted it. As I remember, I just poured "some" in a sprayer, and added water. I get a lot of green growth on my bricks in the rear of the building. The spray turns the stuff black quickly...and it's slow to return.

 

[PaulLovesJamie]

After all, algae loves to grow in chlorinated water doesn't it?

No, I'm fairly certain it does not. If you're referring to chlorinated pools that grow algae, IMO thats because the chemicals have not been adjusted and maintained properly. I've been using Cl in pools for decades and I've never used an algicide.

Interesting idea about the algicide though, I admit I have to wonder if that would work better for the bay floors. Also might be better in situations where you dont want to worry about side effects of Cl (like color changes?).
But Chlorine is cheap and works great, so I probably wont switch, unless I come up with a good reason to.

 

[smokun]

Liquid Chlorine

Try buying liquid chlorine from your local swimming pool supplier or chemical warehouse. Home Depot also carries pool chemicals.

It is more concentrated than bleach. Let it sit for a few minutes; until it turns brown, then hose it off. We use it for getting all kinds of mold, as well as algae.

Wear eye protection!

 

[mjwalsh]

This may be elementary but I was wondering what gets the green algae off the floor and concrete walls? I spray it off several times a week and it still comes back. Looks black in some places and green in others. Anybody have any tips? Thanks in advance.

cdreed,

http://blackmold.awardspace.com/kill-remove-mold.html

According to the above linked document, it looks like there are bunch of solutions. After reading & having used chlorine bleach many times ... I am leaning towards using hydrogen peroxide next time around. It seems like it might have a longer lasting effect in terms of prevention. I am not sure how it will compare cost wise though. The article explains that the roots have to also be killed for the mold or algae to not just come right back immediately.

mike

 

[smokun]

Don't Forget To Brush

Just like the dentist says, you need to brush the chlorine. Sorry I didn't mention it initially. The mold or algae may be in the pores and need a penetrating friction to loosen and permeate the growth base.

Good Luck!

 

[MEP001]

Just like the dentist says, you need to brush the chlorine. Sorry I didn't mention it initially. The mold or algae may be in the pores and need a penetrating friction to loosen and permeate the growth base.

I don't agree. I never brush it, I just spray it on the bay floors late at night and leave it. The normal bay use is enough to flush the dead algae bits away. The fact that it roots into the concrete is exactly why I don't rinse it off.

 

[soapy]

It is pretty easy to sprinkle on some granulate chlorine that they use for hot tubs and swimming pools. I do it at night and it sits around on the surface slowly disolving. Has a longer lasting effect compared to liquids IMO.

 

[Jeff_L]

Yep - just as I thought, we all have different solutions to combat algae. Looks like they all work well enough for each of us.

I take a cheap route and it works for me. I buy the cheap bleach at Costco, mix 4 parts water to 1 part bleach in a residential pump sprayer you would use for weeds. In preparation I shut down the bay and let it dry, then spray the green stuff and just beyond it, and let it sit. I don't rinse it at all. This allows for the bleach to get into the pores and usually lasts for quite some time. I re-open the bay once the green is gone. On a sunny day this could take 5-10minutes.