Highly recommend. This product worked great. Iron had gotten into our pool water from a patio umbrella I mistakenly thought was aluminum and had placed in the opening we have on our Sun shelf for an umbrella. The bottom of the pole had started to rust. Our pool holds almost 8,000 gallons of water and it is gunite. With the chlorine levels very low I poured an entire bottle all around the pool perimeter and left it overnight. In the morning all the staining was completely gone. Looked like when it was new. I brushed the pool two days in a row to make sure all the chemical was dissolved into the pool water. It's still looking great! So easy and I didn't actually follow the label instructions. Highly recommend.

Put this in the pool and was not convinced it would do much as just a few sprinkles around. I came down first thing and was initially disappointed as had not really changed. Went out in the morning and got back a few hours later to find a totally clear pool. Sorry i did not have the before photo. Recommended if the stain is metallic and this product is suitable!!

Didn’t remove the staining on the bottom of our pool would not buy again

First of all this stuff is amazing! I was skeptical at first, but read a TON of reviews. I had some weird stain on my sand colored fiberglass pool which is not yet 2 years old. With it being a sand colored fiberglass pool it was hard to see the stains at times so I was not sure how long it had been there. Mainly the stains were on the edge of the stairs, shallow end where you step off the stairs on the floor of the pooll and sides of the pool where my safety ledges are. So mainly in the shallow end of the pool. I thought well all high traffic areas maybe dirt scale and then my husband had used a tanning lotion that had a bronzer in it so I thought that had attached itself to the pool.I tried the Jack's Magic testing kit which yielded no results on what the stain actually was. I had tried a ton of stuff like a sequestering agent, keeping chlorine levels low, scrubbing etc. I even showed pictures to where I get my water tested and they had no idea what it was and said they could send pictures to a stain specialist. However that I might have to just live with the stains. After weeks and weeks of no stain specialist coming out and the stains still being there I was desperate. I was mad at myself trying to figure out what we may have done to cause the stain.I bought this stuff and got my chlorine level down to 1ppm and put a whole container in the pool. Ran the pump to circulate an hour then cut it off and waited 12hrs with no pump running. Next morning was kind of upset still saw stains brushed the pool all over 2-3 times a day at 48hrs the stain on the bottom of the pool was gone! During this time I ran the pump 12hrs during the day and it was off 12hrs at night. At 72 hours the stains on the ledges of the stairs and safety ledges were about 80% gone! Keep in mind I brushed this pool everyday 3-4 times a day and tested the water about that many times as well.The citric acid will eat at your chlorine so I had to play with my automatic chlorinator and dial slightly up then down to keep the chlorine at 1ppm. The citric acid will also keep your PH low like 7.0 to 7.2 which for me was the lowest it had been the whole time the pool had been put in. We usually run around 7.6 to 8.2 and I swear I was using PH reducer several times a week to get it down to maybe 7.6 for a few days.Don't be alarmed your pool water will also turn slightly cloudy at day 2. At this point I don't care that will clear in due time. So be patient let it do it's stuff, brush your pool alot, don't shock for a week and don't use the pool during this time! It will clear up your stain. We believe our stain may have been dirt trapped by scale in the pool due to the high PH over the course of the year and a half.

So I see some bad reviews of the product. Likely folks who aren’t:PatientUsing it correctlyUsing enoughUsing for right reasonBecause I have used at least 4 bottles in the last couple of years and it is exceptional.When you Uber-shock the pool, like a SLAM that has FC at about 10,000!!!! You will plate the pool. The pool will turn brown and you will be angry. Algae gone yes, walls and floor and steps now cocoa brown. I thought it was metals but in my case it has always been a stupid learning curve on a proper SLAM and detecting when algae is actually alive or when it’s dead and just needing removal from water. Always: at pool opening in March or April!On my last plating of a Catalina Fiberglass pool that was exceptionally blue, I opened the bottle and cut a small triangle opening maybe 1/4 inch tall and 1/4 inch wide. Use the bottom to sprinkle the acid as close to the wall of the pool as possible. This puts granules and high density citric acid right on the affected area. It’s not usually instant especially if plating is heavy, but I have seen it erase the wall instantly on very mild problems.I treated the steps at 6 pm. I waited until 8 pm and inspected. No results. I salted it again, but this time a small bolus was dropped at the middle of the top step. Still no activity. 10 pm, nothing. I go to bed knowing that plating is bad. 6 am, look outside, there is a nearly iridescent blue skunk stripe from the top step down to the pool floor. I retreated the NOW thinly plated steps and shallow end walls. PH had risen and the bolus had by gravity washed its way down about 6 feet past steps. Home from work at 5 pm, found the entire shallow end walls very thin, steps completely clean and blue, stunningly so. I used the balance of the bottle to treat the shallow walls to midline of pool, hits the corners heavier, step vertical faces. While I was working outside the pool simple snapped blue to the drop off. Period- end of story.The second bottle, half was used for the deep end walls BUT- the acid had crept to the deep end and thinned the plating slightly already.The deep end is always more difficult as the acid will settle to the bottom radius and not stick to the walls. That’s ok. The whole pool with 1-2 bottles used will, in a matter of a day or two, be completely clean.Anything above the water line: like you let the water drop before treatment or the foray two inches that usually don’t get concentrated enough——Mix in a bucket a few ounces of the acid with 1/2 gallon of water. Lower your water level to explode the entire upper region needing treatment. Let it stay dry. Do not splash water on it. Use a 1970s sponge mop, soak with acid, mop the walls but don’t dip the mop in water. You want full concentration. Let the sun see the all’s for a bit if you can. Heat intensifies acidic reactions as a catalyst. It can’t hurt the walls at all! Mop repeatedly round and round trying to keep the area damp with acid solution. I’m two passes at noon with good sun, you will see a clean wall like it was painted. Hose the wall down to rinse acid, restore water level above the normal line, adjust your PH and Alkalinity back to correct.Then don’t shock the heck out of your pool again!Ascorbic acid will best remove iron/rust stains. Similar products are avail in ascorbic acid. Same application, including the mop. It will too clean the walls the same as citric, but more expensive.4-6 ounces of HCLin 2 gallons of water will do the same BUT——- you better be on your game for PH and Keep chemistry up. The HCL will perform as well or better than both alternatives but it will also expose the pores of the gel coat and you will likely plate easier heretofore.The stuff is a miracle drug for the pool. Be patient. Leave the pool pump off and stagnant clean correct PH water to start and leave it as needed for two days to get the performance. It’s not a microwave oven!!!See ya- I need two more bottles for 2023 just in case.