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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 products are harbor safe and eco friendly!

Marine 31 Mildew Remover 20 oz.
Item #: M31-370
Our Price: $19.99
Availability: Usually ships the same business day

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Product Reviews

68 Reviews
91% (62)
3% (2)
3% (2)
0% (0)
3% (2)
93% Recommend this product (63 of 68 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)
Great stuff
Best stuff ever for removing mildew! Better than bleach!
North Carolina
Very good
Only thing I found that really works.
Ravenna, Ohio
Best I've found
This mildew remover works great, it's the best I have found for removing mildew from my boat seats. Be careful to use gloves, wear old clothes and cover what you don't want discolored. This is strong stuff and worked great for me. I sprayed it on and let it set for 5-10 minutes and then scrubbed the worst areas with the scub brush I also purchased from Marine 31. I also wiped everything down with clear water after using this product. I don't know if this was necessary but I felt it would be good to do so. I applied the Mildew Guard afterwards and the seats on my boat look great
Barberton, ohio
SHIPPING WAS FAST. Marine 31 is a Great product, It works GREAT. I spray Marine 31 on a golf cart , everyone thought it was a cream colored golf cart. I let in soak in for 10 to 15 minutes and the golf cart was actually white, the seat came out white also. I will buy this product again...
ProsMarine 31 does the JOB. IT WORKS!!! Let it soak in 5 to 10 minutes for Fantastic Surprise!
You need more stars
This stuff worked like magic. I had a severe mold problem after some bad weather and torn covers.
I saw a youtube video where a guy had the same problem and swore by your product.
I sprayed the seats and waited. I didn't try to wipe it. In an hour I came back and the seats were like new. The mold, and more importantly, the stains that mold leaves behind were gone.
Erwin Schulz
Awesome Product
We were so pleased with this product, we had such bad mildew on our boat, we sprayed this on and within a minute the mildew was disappearing before our eyes! We will be buying this again in the future. I have never seen a product work so well on mildew as this!! Try it you wont be sorry!!
They should call it "MIRACLE 31"
After multiple attempts and multiple failures with multiple products (3M, Starbrite, spray nine) this magical bottle arrived and saved the day. Worth ten times the cost! THANKS!
Was amazing
Absolutely done the job. I thought my seats were ruined. Spray Marine 31 on and it went to work. Now my seats look brand new again. My girl friend bought other cleaner, it would not even touch the mold. Marine 31 is a superior product.
Woodstock, CT
Best product I have used in 40 years of scrubbing boats!
I read the reviews about the Marine 31 Mildew Remover and still was skeptical. We all have been victims of the embellished claims of manufacturers, right? I had already spend 3 Saturdays scrubbing the interior of my not-so-huge boat! The results angered me. My boat is constantly kept covered and is always wet inside from the kids and their skiing. Long story short, it has never looked this good since I have owned it.
ProsUnbelievably easy to use. Just spray on and WATCH the mold disappear.
Table Rock Lake MO
Works Great !
Nothing I have tried before works like this. Almost effortlessly made seats look new again.
Birch Villa resort Cass Lake
I own a resort and have several rental boats, these boats are used almost everyday throughout the summer. The mildew is horrendous by summers end. So believe me when I say I have never found a product like Marine 31 mildew remover. This is my second year I have used this product on our pontoon boats. I just spray it on and go back and wipe down. It does all the work for me.
ProsEasy to use and fast acting
ConsStrong smell
Easy and quick
Just sprayed it on - let it sit for a while and wipe - and the stains are gone!
Santa Rosa Beach Florida
Excellent product
Excellent product best that I have found for cleaning mildew. Only wish I could find it close by.
Too Easy
Product is incredible and so easy to use. My mildew was very bad and I was very skeptical, but after researching the product, I had to give it a try. Glad I did. Pontoon boat cushions look new!!!
Worth EVERY Penny - Order 1 to use and 1 to save for later
This stuff just flat works. After trying all the brands and nothing worked, including Mr. Clean Magic Erasers and 3M Mildew cleaner and scrubbing. I found a link to this online and ordered 2 bottles. We tried a hidden spot. My husband said, that will never come out. Wrong. Even the spots that were the worst, but hidden are gone. The seats are clean, clean, clean. No harm to anything. Thank you. We thought they were a lost cause. We used 1 bottle and now have a spare in the boat house, just in case.
ProsWorks as described. No harm to seats or surrounding carpet. They look brand new.
Charleston S.C.
Very Good
The online videos show people spraying it on and wiping it right off and Presto! Completely clean. Nope. Gotta let it sit for a while then scrub pretty hard with a stiff brush. After a while you get the mold and mildew off but it still takes work. Also, the smell of this stuff is Strong! I think it is probably the better of the products offered out there...
Cheryl, Irwin, PA
Miracle Product
I never take the time to write reviews. However, this product certainly deserves one. My husband and I have tried every mildew remover product out there. Nothing worked. I came across this site online and read other's reviews. Decided to try one last product before giving up. This is truly a miracle product. One piece of advice---wait the 3-5 minutes after spraying. then use either a scrub brush or scrub pad. You will not believe the difference. to all you boaters---this is definitely worth the money. I just ordered the gallon refill jug to have on hand in the future. If your boat interior is bad with mildew, just order the gallon jug. You will use it up fast. It doesn't take off every little spec, but close to it.
ProsIt works!!!
Danbury Wisconsin
Marine 31 Mildew remover
Most amazing product I ever bought. Tried everytning to clean the seats on an old neglected pontoon we bought last summer and nothing worked. I ordered Marine 31 Mildew Remover and the mildew disappeared like magic after spraying it on the seats. They look almost new. I’m going to order the rest of their products to keep the seats looking new and to preserve them.
Bridgeville, DE
Absolutely Unbelievable
I tried 2 other products to remove mold / mildew from my golf car seats, they didn’t work. I even used a “power brush†with these products thinking this would break it up. Not so lucky. Started looking online for replacement covers / seats to resolve my issue. My wife was also searching online for another type of cleaner when she came across a video of someone using Marine 31. In the video, it was hard to believe it was so easy to use and worked so well. We ordered some and It worked better than one could ever imagine. Sprayed it on, let it set for 3 minutes and wiped it off. UNBELIEVABLE, the mold / mildew was completely gone. I was amazed ! This product absolutely does what it claims to do, remove mold / mildew. I have already recommended it to a friend of ours who owns a marina, sending him a video of the results. Thanks Marine 31 for saving us both time and money.
We only ordered one bottle to make sure we were not wasting money on something that didn't work, because we had tried everything already. We will be ordering more, this stuff is amazing and it does everything it says. Our boat seats look like we replaced them with new ones, but all we did was use marine 31.
Lansing, MI
Marine 31
I purchased a large bottle of Marine 31 in June but did not use it until today Sept 28 as I winterize
the boat.
I am totally shocked at how fast this product made the mildew disappear.
Four minutes I would guess with no scrubbing...I was floored.
I spent the whole summer apologizing to my lake guests regarding this black mildew on my bimini
I considered purchasing a replacement fabric for my bimini top this fall.
Wow, wow and wow I'm overjoyed!
This really works!
I keep my boat on a covered lift but there is often condensation on the seats and they get mildew on them. I’ve tried lots of products and nothing worked very well until Marine 31. Wow! I sprayed it on, let it sit a few minutes and you can see the dark stains disappear. Just wiped it off and the seats look like new. I was actually considering having the seats redone but this saved me $3700.
West Allis, WI
Works as great
Product works great, however I do wonder how a product that requires gloves and That you have to avoid breathing in, can be environmentally friendly.
Lake Martin, alabama
Are you kidding me!
Marine 31 is incredible! Easy on easy off, gone! Thanks to marine 31. I have to try some of their other products!
Minocqua, Wisconsin
Marine 31 Mildew Remover
I was amazed at how well this product worked. I had tried everything to remove the mildew from our pontoon vinyl seat. I let the product on for 5 minutes and then removed the mildew. I have already recommended it to two of our neighbors with boats.
ProsIt worked.
ConsA couple of spots remained but I hope to apply it again to see if I can remove them.
New Hampshire
Did absolutely nothing on our seats and vinyl at back of boat. Used twice and nothing
Very disappointed haven't tried the mildew guard or conditioner as mildew still on there
Orange Springs FL
Best Product EVER!!!!!
First let me say, we have tried for years to remove the mildew from our boat seats and nothing worked. Marine 31 Mildew Remover is a miracle!!! We were amazed at how easily it removed the mildew and mold. I ordered a gallon!
Thank you for such an awesome product.
Melbourne, FL
Works like a champ
Great stuff period. Wasted lots of time and money on other products for years. Marine31 mildew remover did the job in seconds flat.