Oxalic Acid (8 lbs) 99.6% Pure - Metal & Wood Cleaning and Bleaching, Rust Removal (C2H2O4) - HDPE Container w/Resealable Child Resistant Cap

This worked perfectly to clean my front porch off before staining. It took a lot of the years of grime off and make my wood look good as new. Simple to use and a great value

Helped with a stained wooden floor.

Living rural, on a well, sometimes leaves one wondering what to do about the never ending rust stains in the toilet bowls. There are sprays and powders and they all contain the same MAJOR CHEMICAL as this bucket. So why not make your own, only better? Within ten minutes of getting this, a scoop was in both toilets doing its job - one in the tank, one in the bowl. A few hours later the rust was 90% gone and we were back to pretty. I have used this stuff on rusty metal files, tool surfaces.... anything with rust. Once done wipe off and spray an oily film to protect. Best to try on a small area first. Wear gloves.... and for God's sake, wear eye protection - this stuff is unforgivable.

Was looking for Oxalic acid to treat honeybees. I have bought other brands and it wouldn’t stick in the applicator tube. This does. So if you are buying for honeybees, this brand works well.

After sanding to remove water rings from an oak table, I was left with a 4" dia dark black ring stain (about 1/4" wide) that penetrated the grain. Hydrogen Peroxide did not make a dent. I applied this product, dissolved in hot water, to paper towels placed in the area of the ring and left to soak for a couple hours. That effort removed 80%. Next I wet the surface with the same mixture and sprinkled some dry oxalic crystals directly to the liquid over the ring and following grain lines crossing over the ring (to distract from potential over-bleaching in the shape of the ring). After a couple more hours, I rinsed with cold water. After the water dried, the ring completely disappeared. It reappeared faintly during staining, but 99% disappeared again (maybe even over-bleached in some areas?) after stain & subsequent poly coats dried. Now I'm just sad I did not take a before picture. I really did not think the ring was removable and am very happy with the result (photo).

Update: This year I used hot water from the tap, filled a 1 gallon plastic bottle and added 16 oz. of the acid and the hot water in a 5 gallon bucket and it dissolved quickly. I also put some Dawn liquid dish soap to help it cling to the surface. I added a before and after picture so you can see how well it works. No scrubbing, just spray on (I use a 1.5 gal. Garden pump sprayer), wait a few minutes and rinse. I did use a pressure washer first to remove the heavy scum. I use this to remove the algae growth from the bottom of my boat at the end of the season (it sits in the water from May to October. The only issue I have is that it doesn't dissolve easily -it's recommended to use hot water but I'm using a 5 gallon bucket which doesn't fit in the sink. But, that stated, it does a great job of removing the scum and algae. I pour the mix into a garden sprayer (a gallon at a time) and spray onto the bottom of the boat and then hose if off a few minutes later. I rarely need a brush. This is a much more economical solution than buying the ready made products sold in squirt bottles.

Didn't work like it shows in my opinion maybe I didn't mix it strong enough I'm going to try it again to see if it works better at double strength I did not do any prep work to the fence previous to spraying it so that may be my problem

I used this product as a neutralizer (whitener) after cleaning my cedar siding with OxiClean. Using this product is much more economical to use then branded products indented for the same purpose. There are several cleaning products in which the active ingredient is Oxalic Acid.

Worked well cleaning teak