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Marine 31 Mildew Remover 20 oz.

Marine 31 Mildew Remover 20 oz.
Remove stubborn mildew stains – FAST!

Marine 31 Mildew Remover quickly and safely removes stubborn mildew stains on virtually all marine surfaces, including vinyl seat cushions, rubber fenders, fiberglass, gel coat, canopies, and more! Marine 31 Mildew Remover forgoes volatile cleaners and instead relies on smart chemistry; even severe mildew growth is no match for the incredible cleaning power of Marine 31 Mildew Remover.

Marine 31 Mildew Remover is the best boat mildew cleaner available!If you’re a boater, chances are you’ve dealt with stubborn mildew stains on vinyl cushions. If you’re reading this product description, chances are you’ve been less than satisfied with the performance of other so-called marine mildew cleaners. Fortunately for you, we’ve compared Marine 31 Mildew Remover against other marine mildew cleaners and have found that it removes mildew stains faster, with less effort.

Not all marine mildew removes are created equal! Most over-the-counter marine mildew cleaners rely on heavy concentrations of bleach and other volatile chemicals that actually cause more harm than good. Marine 31 Mildew Remover removes stubborn mildew stains without discoloring, dulling, or drying out vinyl surfaces. Best of all, it still retains the powerful cleaning ability to remove mildew stains – FAST!

Use Marine 31 Mildew Remover on:
  • Vinyl cushions and chairs
  • Rubber fenders
  • Fiberglass
  • Gel coat
  • Canopies
  • Boat tops
Marine 31 Mildew Remover works wonders for household cleaning as well! Use this professional strength formula to clean tile, grout, showers, bathtubs, counters, and sinks.

Marine 31 Mildew Remover works FAST!Directions:
  1. Spray directly onto surface and allow 1-3 minutes for penetration.
  2. If necessary, agitate surface with a brush or terrycloth towel.
  3. For stubborn stains, allow cleaner to penetrate for 5 minutes before agitating.
  4. Thoroughly rinse and dry surface.
  5. Follow with Marine 31 Mildew Guard to protect treated surfaces.
20 oz.

Made in USA

Marine 31 Mildew Remover 20 oz.
Item #: M31-370
Our Price: $21.99
Availability: Usually ships the same business day

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Product Reviews

97 Reviews
89% (86)
4% (4)
2% (2)
2% (2)
3% (3)
92% Recommend this product (89 of 97 responses)
Pittsburgh, PA
Magic in a bottle
We pulled our boat out of storage last week and all the vinyl was covered in mold and mildew. After 2 hours of scrubbing with mold and mildew remover and then trying a magic eraser - I was very upset thinking we would have to have the cushions recovered. The mildew had stained all the cushions and I couldn't get them to come off. I found this product online and figured I would try it before searching for someone to recover our seats. This stuff is MAGIC! I didn't even have to scrub the spots. It took awhile for the stains to disappear - but after about 15 minutes - every single spot was GONE! I will buy this product every year - and I am going to try the mildew preventer before we put the boat away at the end of the summer. HIGHLY recommend this product!!
Lillington NC
Marine 31 Mildew Remover
Absolute wonderful product. For health reason, boat sat for two years in North Carolina's humid, moist weather. Was covered with canvas boat cover for 1 year. Last year sat out in elements uncovered. In effort to clean, I researched internet and decided to test four methods of removing mildew: 1) Marine 31; 2) 3M mildew remover; 3) comet spray gel (vinyl only); and 4) magic eraser. Applied all 4 products to boat platform, left for 5 to 10 minutes. Marine 31 results were unbelievable. Person that was helping me could not believe the difference in the results as compared to the others. Family and Friends that have visited, I take them out to see the boat. Also boat owners, they understand the effort and frustration in trying to removed mildew/mold. Needless to say, they have ordered the Marine 31 to clean their pontoon. The mildew//mold on platform was heavier, darker, and thicker than what is shown in the cushion pictures below. It was just the only items I didn't get cleaned before I ran out of Marine 31 and have reordered. A picture is included to show how great the platform looks now. Like New. It was only when I was reordering to complete the project (cushions shown) that I decided I had to write the review. So wish I had a before and after on platform. Writing reviews is out of character for me, BUT I had to let others know. I have invested too much time in previously cleaning our boat and by no mean got the results obtain with Marine 31. The Marine 31 actually removed the gray spots left from previous cleanings where mildew stain could not be removed. The boat is a Renken (oldie but goodie) with lots of wonderful memories. My excitement from using the Marine 31 Mildew Remover has given me such confidence in this Brand that I will be ordering their oxidation products.
ProsQuick, efficient, and does the job. Spray on, leave 5 to 10 minutes, wipe off Cleans much older (gray) mildew stains that were left when previously clean the boat (3 years ago)
Greenville SC
Absolutely fantastic product
I've been struggling with the cleaning of moldy and mildewed vinyl seats for over 25 years. I have tried just about every cleaning product out there with mostly disappointing results.

I purchased Marine 31 after seeing stellar reviews and expected nothing better than the others. I sprayed the cleaner on my very nasty seats and console then went off to do other boat related tasks. When I came back 5 minutes later the vinyl was 95% clean. No scrubbing, no swearing, awesome.
ConsA bit pricey
Alma Georgia
The beat
Don’t waste your money on other products like I did. After frustrating myself with trying everything imaginable, I ordered this as a last ditch effort. My boat seats look new again!! Just trust me. This stuff is wonderful.
Bushnell, Illinois
Great Product
I've been around boats 34 years, only thing I've seen that actually works the first time!

New Jersey Shore
Amazing Results
When removing winter shrink wrap each year there is always significant mildew on the padded interior of the boat. I sprayed the passenger side, turned and sprayed the driver's side and in that short time the original mildew (passenger side) was gone! Not just "better", gone. From just about totally covered to white again.
Works amazing
I had black spot from two years ago that I scrubbed with other products and was unable to clean, this stuff took it off in minutes with very little effort. Make sure your in a well ventilated area or where a mask!
North Carolina
Mold killer
Sprayed it on mold between my leaning post seat and it was gone in a minute
Corpus Christi, Texas
Never believed that it would work as advertised
AMAZING. Vinyl Boat seats were heavily stained with deep dark mildew spots, literally everywhere. I had tried several other products and has scrubbed and scrubbed with absolutely zero results. Then i came across Marine 31. I was very skeptical that it would produce the results that i had read ans seen, but this product actually worked as advertised. No scrubbing whatsoever was even necessary. Sprayed directly on the seats as instructed and then watched the miracle take place. Well worth to $20.00 investment, as i was literally shopping around for prices to have the seats recovered.
ProsSuper Simple, and it ACTUALLY WORKS
Wow wow wow
All I can say is wow. Great stuff. Saved me thousands not to do my seats a recover
Chapin, SC (Lake Murray)
Absolutely amazing!!!
My boat was embarrassingly nasty. I am providing before and after pictures. I tried every commercial product I could find and many home remedies, including hydrogen peroxide, clorox both diluted and undiluted, muriatic acid, vinegar, you name it. Nothing worked. I decided to try Marine 31 but I was skeptical. Well, it works beyond my wildest expectations. I am ordering two more bottles today.
Turns out I could only add three pictures so one "after" is missing but you will still see the results.
ProsWorks as advertised. The best I have found
ConsExpensive (but I guess it's worth it.)
I really wanted this to work!!!
Maybe my expectations are to high. But after watching YouTube reviews of this product, I thought it would take out the mold stains. But after trying it again and again, it DID NOT take out the mold stains on my vinyl boat seats

I am referring to the dark spots and their removal. I first clean the area, then after that area dried, I sprayed on the the remover, waited 15 min, agitated the area with a brush and rinsed. No noticeable difference from before and after.
ConsDid not work for my mold stains on my vinyl seats
Marina del Rey, CA
I saw Marine 31 on a on-line video. The user was very enthusiastic about the product, so I gave it a try. I had severe mold issues on my vinyl seat cushions. I had tried 303, vinegar, bleach, oxyclean, nothing worked. I sprayed the Marine 31 on, let it set as directed, and wiped it off. Honestly, it was that easy! Done. The cushions are perfect!
ProsReally easy and effective.
palm coast fl
this works great
i tried many other items and this was the best
Greenville NC
Awesome product
Took the mildew right out of my boat cushions. Had to let it soak a little but did the job.
Goldsboro. NC
Best Mildew remover I have used
I purchased this product after seeing a video on how it worked . I bought it to remove the mildew from my vinyl Golf cart seats it worked Beverly well . I will recommend this to all my friends .
Wake Forest NC
Mildew remover
Seemed to be nothing but a lot of bleach in the bottle.it cleaned ok but not what I was expecting.
Boynton Beach, FL
This stuff is AMAZING!!!
Have tried just about every supposed mold/mildew cleaner remover stuff on the market. Tried magic eraser, degreaser and mildew remover combinations, I think Z Cleaner with their z-scrubber (basically heavy duty magic eraser) is the only thing that came close but that stuff takes hours of scrubbing. Saw this stuff online, ceraonlynhad my doubts, But figured what the heck and gave it a shot. THis stuff does exactly what it advertises. Spray it on, wait 3 minutes and boom. Mildew gone. My upholstery is back to beautiful again. Thank you Miracle 31.
ConsSmell is pretty strong. Make sure you are in a well ventilated area. Wear gloves and remove jewelry. Wife?s Silver ring is now seriously tarnished. 😕
Salado, Tx
Did not work for me.
The stains on my boat seats are still there. Maybe it's not mildew stains but I'm pretty sure it is. Followed the instructions and gave it several attempts. Can't recommend this product based on my experience.
Wausau, WI
The results don't lie!
I had high hopes of for this bottle of what others called a "miracle". I read reviews, watched video reviews, and was optimistic that it would remove the stubborn mildew from my boat seats (which I had scrubbed and scrubbed with other cleaners before finding this).

Even with all my research, I was STILL SHOCKED AT HOW WELL IT WORKED! Again, I had worked on my seats for a long time with other cleaners with virtually zero results. But after spraying on Marine 31, waiting 3 minutes, and simply wiping off with paper towel, I could not believe how well it worked. Almost 100% of that pesky mildew (which I thought was permanent damage) was gone. The seats look like new! I will certainly be buying this company's protectants and other products as well. It's money extremely well spent.
ProsIncredibly effective, easy to use
ConsA bit costly, but we'll worth it
Riverview, Florida
Great Product!
The interior of my boat was unfortunately covered in mildew. This product was great! I sprayed it everywhere and within minutes the mildew was gone with a rinse of water! I had some stubborn stains and as the product indicates, you spray it, let it sit for a few minutes and give it a little scrub with a sponge - it came off easily. I was very impressed and will buy this product again!
Treasure Island, FL
It’s as good as the YouTube videos that I watched about the product. My seats look like new with basically zero effort.
lapeer mi
worked great on my boat seats. better than anything else i have used
This stuff is amazing. We have tried almost every product there is to remove mildew and this works the best. Just spray the stuff on and it works instantly. Our boat was covered for three months and used a whole bottle on the boat, it looks brand new again. I would highly recommend the mildew remover!!
Greer, SC
Absolutely fabulous!
This product was recommended to us to use on the vinyl top of our car, which had become badly mildewed from not being in our garage. We had tried several other products, some of which helped a little, but there was always a final little layer deep in the roof that would not come off, no matter what. With the very first use, ALL the mildew was removed! The roof of our car looks like it just rolled off the showroom floor! We will highly recommend this product to others and will not waste our money trying anything else. As long as we have this car, we will be loyal Marine 31 Mildew Remover users!
Goodland, FL
Only product to buy
I tried a number of other mildew removal products on the seats of my boat. None of them did the job. I saw a YouTube video of a guy had the same issue as me. He tried the same products without success until he got Marine 31 mildew remover. After I saw his results, I ordered a bottle and it worked great. My seats look good again. I will be ordering a gallon as well as some of Marine 31’s other products.
Orlando FL
It works!
Stored boat with cover for a few months in Florida summer heat and rains. Seat backs had mildew. Much of the mildew came off with white lightening cleaner but stains remained. Bought lime away foaming mildew stain remover several applications stains a bit less but not gone. Bit the bullet ordered Marine 31. Spray it on let it sit a few minutes many stains disappeared but a few remained. Rinsed, reapplied let sit and used tooth brush to scrub it in. All stains are gone. I did get some on my shorts and t-shirt turned them white similar to what bleach does.
Did not discolor my 2017 tan seats.
Newburgh NY
Heavily Mildewed Beige Pontoon Boat Seats: 80% Gone 20% Remain
The stains definitely fade...but not completely. That said, mine was an extreme case as you can see by the "before & after" photos.
ProsRemoves about 80% of a heavy stain
ConsLeaves 20% of a heavy stain.
Lakes of Michigan
Marine 31 Mildew Remover Review
This worked as needed and shown on YouTube. I've used many other products and was disappointed as they wouldn't remove all the mold spots. Marine 31 Mildew Remover got about 95% of them with little effort other than spraying it on. It does smell like bleach but I didn't have any bleach color spotting that I was concerned with. There are no ingredients listed on the bottle. I will continue buying this product as it's the only one I've found to work as I need.
Magic in a bottle
This product is fantastic, works as promised!!
ProsWorks quickly and efficiently