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Marine 31 Mildew Remover 128 oz.

Marine 31 Mildew Remover  128 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 youre a boater, chances are youve dealt with stubborn mildew stains on vinyl cushions. If youre reading this product description, chances are youve been less than satisfied with the performance of other so-called marine mildew cleaners. Fortunately for you, weve 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.
128 oz.

Made in USA

Marine 31 Mildew Remover 128 oz.
Item #: M31-372
Our Price: $49.99
Availability: Usually ships the same business day

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Product Reviews

27 Reviews
89% (24)
4% (1)
4% (1)
0% (0)
4% (1)
96% Recommend this product (26 of 27 responses)
Amazing Product, never used anything better
This product is by far the best to use on boat seats I've ever seen or used. Looked horrible before, like new after use. Simple answer, just give it a try and you'll never buy anything else again. see photos!
Cumming, GA
works great, but packaging is faulty
Gallon container had been opened and 2 small strips of tape to keep closed. There was no sealed vinyl under the plastic cap. Not sure how much leaked out, but paper packaging was all wet.
truly amazing !
WOW, spray on, rub lightly, wait 5 mins. apply again if needed,wash off with clean water,LOOKS LIKE NEW ! I used on boat seats that were badly mildew stained I really didn't think that the stains would come out but totally stain free. Very easy to use, make shure to wear gloves, will cause skin to burn after about an hour or so .Great product that really works .
Little Rock, AR
Amazing Cleaner
I cleaned our boat seats with 31 this past weekend! I was in total awe of how it worked. One spray, one wipe and the horrible mildew was gone! A true miracle cleaner!
Palm Coast
great cleaner
i ordered the small bottle and liked it so much i ordered the one gallon size
Best mildew cleaner EVER!!!
Was able to get 3 year old mildew stains out of my boat seats. Thought it would be impossible until I purchased Marine 31. Now they look as good as new.
ProsReally works
SW Florida
Great product.
Best mildew remover I've ever used, and I've use several different products. Easily removes
mildew stain from marine upholstery. Rather pricey when purchased in smaller spray bottles but
more reasonably priced in gallon containers, especially with a promotional discount applied.
ProsProbably the best mildew stain remover on the market.
ConsOther than price...none.
Amazing Product
It truly works as advertised. Surprisingly very little scrubbing.
Word of caution, if used inside a cabin or other confine area, make sure it is well ventilated.
ProsRemoves the most stubborn mildew stains will little or no scrubbing required.
Kihei. Maui
Leaking bottle in shipment
Shipment arrived intact, one Bottle the lid was not tightened and the product had leaked into the box ... destroying the paper packing ... I have pictures ... it was over $80 in freight... and approx 1/4 container drained ...
great product but poor shipping practices
Gulf shores Alabama
Mildew remover Magic !
I have a wave runner cover I was close to throwing away because of all the mildew on it. I had tried several other products with no results, but then I came across several reviews of Marine31 and wanted to give it a try. This stuff is like a magician in a bottle. You can see the mildew disappear, and my cover looks New again!
Crescent Beach, Florida
It works, pure and simple.
Thank you for developing a product that actually does exactly what it is supposed to do as advertised.
Ordering was easy. We've added your website as a favorite to our system so we can easily re-order when we need to.
Upper Michigan
Works good but needs to sit on material before scrubbing vigorously
Is not spray on wipe off on stubborn stains. Needs to sit on material for 5 mins then scrub vigorously. Clean off with spray nine then clear warm water. May need two applications. Dry thoroughly then apply a quality Vinyl protectant... I assume I had some very stubborn mold stains..
I tried a few different brands but this was the best for my problem. Nothing works without some scrubbing.
ProsDoes work good ..
ConsNeeds ELBOW GREASE ...
Ocean City
Works Great!
I had mold on my T-Top and bolsters. I sprayed on Marine 31, waited 10 minutes and all the mold was gone. Great Product!
Punta Gorda FL
Mildew remover
This is the best I have ever used for getting rid of mold and algae on my boat.
Raystown Lake, PA
Very pleased
I have to admit that I was skeptical when I ordered this but it really did a great job on the mildew that had developed on our pontoon at the end of this rainy summer in Central Pennsylvania. I honestly wish we would have taken before and after pics. We will definitely be buying Marine 31 again.
ProsProduct was thorough and effective quickly
Milwaukee, WI
Marine 31 Mildew Remover
Works as advertised. What took me 4 1/2 hours last year with 3 people cleaning this year took 2 hours with 1 person cleaning. I have already recomended it to everyone I know that has a boat.
Ottawa, On, Canada
Great product, great results!
Rarely have I used a product that works so well. I have tried every other products combination and elbow grease with no results. Marine 31 worked on my vinyl seats on my pontoon that looked awful with black mildew stains, they disappeared within seconds of applying the product and then looked brand new! Very satisfied with the results.
Lake Lure, NC
Works like Magic
Best Mildew remover on the market. Spray, wait and the mildew vanishes. It€™s like magic. For stubborn areas, use the horse hair brush.
So so
Not exactly as strong as the YouTube video made out to be. Seat they sprayed it on was 3 times in worst condition than mine and came clean but I get it and it€™s no stronger than normal everyday cleaning solutions. Little disappointed but knew that what they say and what is is two different things.
Prairieville LA
More the merrier
Really works on stubborn mildew.
Sevierville Tn.
Jo Sevierville Tennessee
Absolutely love this product. Our boat seats are new again. We had tried everything but nothing worked. I googled to see if there was something that we hadn't tried and found a video of Marine 31. I ordered a bottle to see what it would do and we were amazed. Love! Love! Love this product.
ProsIt absolutely works!
Annapolis, Md
Tried the 20oz; reordered the gallon
Best mildew remover I've ever used. Got it for my boat, use it also on deck furniture, shower tile, etc. The Best!
Fargo ND 58102
Marine 31 Better than I expected!
I was ready to have my pontoon seats redone or replaced I found marine 31 online purchased this product . I was totally amazed at how well it works. I had one seat to do when it started raining I continued working in the rain l just couldn't stop cause I was so excited and impressed with Marine 31! I am so impressed with this product that I feel I could sell this product and would like to try some of the rest of your products!5 star product!
Marine31 really works!! Mildew literally just melted off after product application! Highly recommend!
Weeki Wachee, FL
Unbelievable - Mildew Remover that Really Works!
I€™ve been hunting for a mildew remover that actually works for as long as I€™ve owned boats.

After forty-some years, I finally found one.

Marine 31 Mildew Remover is unbelievable; it works great!

It removed some stuff in a couple of minutes that literally NOTHING else I tried would touch!

Our pontoon boat stays in the water year round here in SW Florida, so the moisture (daily morning dew, fog, and lots of rain, plus the humidity) and heat make a perfect environment for mildew to grow.
New Smyrna Beach FL
This Stuff Works
I've purchased many cleaning products over the years and most of the time I am disappointed in the results. If you are a boater mildew is a constant problem. After a few months of neglect my boat had mildew stains on the vinyl seats and coaming bolsters. I used the Marine 31 for the first time and it worked. I was so happy with the results I ordered a gallon jug.
Prosfast and easy
Cocoa Fl
Product that works
It is a pleasure to find products that actually do what they claim to do. This is rare. Marine 31 has so many applications for us. Living in Florida mold is something we battle all the time. We have found that not only does it act as a remover but that it also has a preventative action. It takes longer for mold to grow back after it has been used on a surface. We highly recommend Marine 31 mildew remover.