Wet & Forget Moss, Mold, Mildew, & Algae Stain Remover Multi-Surface Outdoor Cleaner Concentrate, Original, 64 Fluid Ounces

I have wondered if I could make my driveway and concrete areas look better for years, but my husband wasn't interested in doing the job, and for 27 years he took care of all the outside jobs. We hired a pressure cleaning man now and then, but it never lasted and was not cheap. When my husband divorced me in April 2013, I thought, "Why not try this myself?" So I did. Now let me make it clear that I'm not exactly outdoorsy or experienced at such jobs. I've never pressure cleaned a house or driveway, and don't have the equipment for it. So I figured it needed to work just as the name said: Wet and Forget. And I would say that is the beauty of it.So the hardest thing about this product was figuring out how to apply it without a good sprayer. That is half the battle. It's not hard to figure out how to dilute it, and it really doesn't require scrubbing. . . what it requires is time. And a good sprayer would certainly help! This is not the product you buy because you have a large outdoor party with guests you want to impress next week. This is a product you apply because you want your driveway/concrete areas to look great in a few months. This is not a product you apply if you want absolute white glove perfection quickly, but you simply want your concrete to look a lot nicer for a long time without much money or effort.I took some before and after pictures, and the results are dramatic. In fact, the longer you wait, the better it looks. I guess that sun and rain are what make it work. I applied it on Monday, May 13 in the late afternoon and I'm writing this review almost 7 weeks later. My pathetic sprayer didn't work (I had never bought or used one before, so don't even think about one of those battery-powered Amdro Sprayers from Walmart--they are not any good), so I emptied and washed out a bottle of Fantastic and filled that spray bottle with the solution, diluted according to the directions. Obviously, I couldn't get much done that way, and realized I would need to find a better sprayer. But I was determined, and there were some seriously darkened, moldy-looking white urns beside my garage door that I sprayed well and some of the concrete around them. I sprayed the white garage door of our storage shed as well. I was by no means very good at this, and decided to do an experiment with the last half of the bottle, since my hands were cramping from trying to use the Fantastic bottle for so long.There is a concrete pad in my backyard where my ex used to keep a gigantic telescope that is now gone. So I poured the rest of the bottle on half of it a little at a time, spreading it with a stiff broom brush. After 7 weeks, the results are dramatic. The urns and garage door and concrete around them look so much better. The concrete telescope pad is nearly white on the treated half, and still ugly, stained and dark-looking on the other half.Two weeks ago I used another very bizarre sprayer my ex left behind called "The Chameleon," to do the rest of the driveway. This sprayer hooks up to the garden hose, making it very chancy that the ratio of water to Wet and Forget is correct. This is another sprayer you should not buy, and I can see why my ex left it behind. Anyway, the driveway looks a little cleaner and brighter every day after 2 weeks. My conclusion is that if you have a good backpack sprayer, and want to see your concrete looking better by next season, you will be delighted. And even if you inept, you will get results. However, do yourself a favor and buy a good sprayer. I plan to buy a good sprayer for my weeds and another bottle of Wet and Forget to finish what I started.

Watching a few YT reviews of this stuff, one made the comment that the 'concentrate' ( ie: not the hose end sprayer kind) worked better on their roof than the other version. Both do work, but the concentrate is supposedly stronger.So, we got both. ( Can use the sprayer kind on the house...)Mixed up a five gallon bucket with the recommended proportions of concentrate to water (gave a bit more of the concentrate just because)... filled the bucket about half way... grabbed a long handled brush (car wash at home type brush) and went out onto our north facing porch roof where moss and scales were present on the section that wasn't pre power washed.Directions say to 'soak' the water formula into the shingles, and it does stay in place... for the most part. (Dirty water will run off the roof... in fact, the water will get disgustingly brown... but keep soaking all of the shingles.)Also did another section of a lower roof with another batch and still have about 1/3 of bottle left.Looking at the treated roofs through our windows a few weeks later, we can see the scale area has dried ... the moss isn't there... but it is nice to know that the product is working (it was soaked into the shingles) and will continue to work using a chemical way to kill the scale and moss growth.We didn't treat the main roof of our house, only the north facing lower roof areas that had moss/scale that we could reach ourselves or by using a rented lift we had for another project. For hard to reach high areas, we would consider using the hose end spray version of this product.Next treatment for the lower roof sections ( next summer or so) we will use the concentrate again. Good stuff.

I was very very skeptical of this stuff the first time I bought it. Didn't really expect it work. Three months later, I am a true believer. To quote the old TV huckster, it really does the job!. In this case, sidewalks and driveway in front my Florida home, where algae stains are a never ending problem. They will literally turn everything black in a few years if you do not clean them. I used to spend hour upon hour pressure washing them and then treating with bleach. Good for a year if you were lucky and then had to do it again. Pressure washing worked quite well when the home was newer but after 30 years, the black stuff was so deeply embedded, it became impossible to really get the surfaces clean. A solid black lichen (I guess) was particularly problematic. Pressure washing had no impact it all on that. And it grew worse over the years.No more. The stuff is no match for Wet and Forget. Killed it dead, dead dead. Just faint shadows of the once solid black spots remain now. The only down side to this stuff is it does take a LOOOOONG time to work. Months. Plural. Three to six. Which means the change is very gradual. No instant gratification as you get with pressure washing. But its also a LOT less work. Mix, spray, saturate surfaces. Walk away. It smells pretty bad too and that lingers for a few days. The only other caveat is you should not expect a return to like new condition. Some stains will remain after one treatment (perhaps a second treatment will improve that). But it is arguably cleaner than by pressure washing. Also, go for the bigger size if you plan on doing a driveway. Three gallons (mixed) is not enough for my big driveway and walk.UPDATE: A year later, I am even more of a true believer. My driveway and front walk are as close to looking brand new again as it ever will be, given they are almost 30 years old. Wet and Forget has banished all the previously unremovable algae and other deeply embedded stuff that once laughed at my pressure washer. My only caveat is that to get it all really sparkling, you still have to pressure wash it once in a while (once a year) to remove the surface cred that always comes back if you live in wet climate. The difference is that cleaning is much faster and when you are done, it actually looks clean. Before Wet and Forget, cleaning took much longer and while the surface dirt was gone, the deep down stuff remained so it still looked dirty. I will probably retreat to keep the worst stuff from coming back