Luonix, Vitamin C Powder, 8 Lb

Works like a dream but getting the cover off was a nightmare. Great price

I bought this stuff to try to remove stubborn rust stains from the bottom of my Gunnite pool. It worked well! I turned off the filter, poured a cup or two of the powder over the stained areas, and let it sink. After two days, my plaster looks good as new. No scrubbing! It also removed every bit of free chlorine from the water though. I had to shock my pool twice to restore adequate levels. Also made the water a little cloudy, but the filter seems to be clearing it up (slowly). July 24, 2025 Update: I had to use a LOT of chlorination to get my pool back in balance. The chlorine level got so low I got an algae bloom. I had to buy more chemicals to kill the algae followed by hand-vacuuming to remove the sediment (dead algae). Vitamin C is a miracle for removing rust & mineral stains. ZERO scrubbing, and my plaster looks like new again. BUT...ascorbic acid wrecked the chemistry of my salt pool. It was like starting over again with stabilizer, hardness increaser, clarifier, algaecide, and many baggies of shock. I still recommend ascorbic acid for getting rust stains out of your pool, but be prepared for the algae mayhem that follows!

I've been taking care of a stained pool for the past 9 years, watching it get slightly worse each year. This year I finally decided I had to get a new liner and paint the stairs because it was just too far gone. I heard about Vitamin C on an internet search and bought this just to try since I'm getting a new liner anyway. Long story short, the steps now look like new, the liner staining is gone, and my kids can't believe how blue the pool is. Can't believe it took me so long to find this, but glad I did.

So I had rust and iron stains all over the liner of my pool. I Have a17 foot round pool, approximately 8000 gallons of water. I used one entire bucket, rust staines were completely gone within an hour. Started to work immediately , would buy this again in a heartbeat.

Our liner is 4 years I,d and quite faded. Last year I noticed it starting to yellow which was even more disappointing than the fading. This year I thought I should address it. I had some Vitamin C tabs so I rubbed it on the discoloration and it removed most of it. I could figure out how we had metal in our water until realized my husband had been washing the pool filters with well water. So I did a little research and bought this. I used about half the container for and 18000 gal 18x33 pool. I probably didn’t need to use that much even and I let it sit for 10 minutes or so and when I came back out I could see a lot of the yellow was already gone. Within another 10 minutes the liner was back to blue and the water looked clear and beautiful. I added Periodic Products Culator to my pump filter to absorb the metal from the water. I’m not sure how that will work but 3 days later, so far so good. No more staining yet. The ascorbic acid did drop my ph and my free chlorine, but I let the swg and pump run for the last 48 hours and things are perfect now. My pool looks amazing!

i use it in my swimming pool it makes it crystal clean !

We've struggled with metal staining in our pool. I've used the metal stain remover from the pool supply companies (citric acid) with minimal success. I use Metal Out weekly; I use the clarifying shells. My husband saw a little video online that showed testing the stain with a vitamin C tablet, it said if the stain was truly metal the tablet would dissolve the stain almost instantly. I tried it, it worked. So I bought this Vitamin C Powder, not expecting a huge improvement, as I've been using citric acid from a pool company....two hours later, a perfectly clean liner. NO stains. I used half the container in an 18,000 gallon pool. Really impressive. As another review noted, it did take the other chemical levels way low, but I can fix that with a little patience, a couple of shocks and some baking soda. It was really like a miracle. I'll never go back to using powder meant for metal stains, this stuff is way more economical and so much better.

Worked perfect for our stained pool.