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Harbor Safe Marine Care Products
Waxes, Cleaners & Polishes

68 Reviews
91% (62)
3% (2)
3% (2)
0% (0)
3% (2)
93% Recommend this product (63 of 68 responses)
By Terri Sue
November 7, 2018
Great stuff
Best stuff ever for removing mildew! Better than bleach!
By Bobby Amerson
North Carolina
November 4, 2018
Very good
Only thing I found that really works.
By Walter
Ravenna, Ohio
October 31, 2018
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
By Don Caudill
Barberton, ohio
October 28, 2018
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!
By Erwin Schulz
October 27, 2018
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. Awesome! Erwin Schulz
By Amber
October 26, 2018
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!!
By Chris Kruysman
October 26, 2018
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!
By Steve
October 25, 2018
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.
By Jill
Woodstock, CT
October 25, 2018
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.
By Wes
Table Rock Lake MO
October 19, 2018
Works Great !
Nothing I have tried before works like this. Almost effortlessly made seats look new again.
By Sabrina
Birch Villa resort Cass Lake
October 19, 2018
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
By Gilbert Von Vogt
October 18, 2018
Easy and quick
Just sprayed it on - let it sit for a while and wipe - and the stains are gone!
By Joe
Santa Rosa Beach Florida
October 17, 2018
Excellent product
Excellent product best that I have found for cleaning mildew. Only wish I could find it close by.
By Riney
October 14, 2018
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!!!
By Kathy
October 11, 2018
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.
By Ron
Charleston S.C.
October 7, 2018
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...
By Cheryl Martin
Cheryl, Irwin, PA
October 6, 2018
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!!!
By Connie Kevan
Danbury Wisconsin
October 5, 2018
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.
By Keith
Bridgeville, DE
October 3, 2018
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.
By Lana
September 30, 2018
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
September 28, 2018
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 top. I considered purchasing a replacement fabric for my bimini top this fall. Wow, wow and wow I'm overjoyed!
By Gary
September 28, 2018
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.
By Kirk
West Allis, WI
September 26, 2018
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.
By Jeff
Lake Martin, alabama
September 25, 2018
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!
By Marcia
Minocqua, Wisconsin
September 22, 2018
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.
By vJ
New Hampshire
September 20, 2018
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
By Diane
Orange Springs FL
September 19, 2018
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.
By John
Melbourne, FL
September 19, 2018
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.
By Neil
Mooresville, NC
September 16, 2018
Great Product!
I had given up on being able to clean my pontoon seats. Last chance try with Marine 31 was a huge success. Ended up having to buy the galloon refill to finish the work. All of my slip neighbors were shocked at the results. They are all now first hand witnesses to your products performance.
By Matt
September 13, 2018
Best for vinyl
Tried many other products. This was the best at removing stains without discoloration of the upholstery. Highly recommended
By Lori Lamoreaux
September 5, 2018
Works great
Removed all mildew in boat seats. Works as advertized
By Jo
September 5, 2018
Marine 31 Mildew Remover is the BEST
Marine 31 Mildew Remover works better than anything that I have ever used to remove mildew from boat seats. Wish that I had known about this product sooner, it could have saved me many hours working to clean the boat seats. Other products that I used did not work nearly so well and required a lot more effort on my part.
By Jason
September 2, 2018
This stuff is awesome. I didn't even need to scrub it in order to remove the black spots.
By Matt
Athens, Georgia
August 31, 2018
Amazing product
I actually bought the marine 31 for my golf cart. Its been years since I cleaned the seats and they were really black from mildew. I tried many things but nothing worked. I almost gave up but decided to give marine 31 a chance and the results were unbelievable. I sprayed the front and back seats and by the time I was done spraying the back the front almost looked like new. I hardly had to even wipe them. I wish I would have taken before pics.. I got some after the fact and all I had to do was wipe them dry!
By rick
Southern Illinois
August 28, 2018
amazing product
After using everything I could think of to clean my pontoon seats with no luck I saw a comparison video with 4-5 products and marine 31 was the clear winner so I ordered it. Let me tell you it is amazing.Simply spray on seats and watch mildew get lighter, after 3-4 minutes hit stuborn spots with a soft brush, rinse off and towel dry. Get Marine 31 mildew remover, IT WORKS
By Cathy & Bill
Hilton Head, SC
August 25, 2018
No other product out there compares! We thought we were going to have to replace our boat cushions because nothing we tried would touch the black stains. This product is magic!
By Liz
Orange Beach AL
August 23, 2018
Can’t go wrong with product!
This is a great product! We tried several others to clean our boat seats and none worked. This product works and we will order again!!
August 20, 2018
By Ken
Owasso, Oklahoma
August 18, 2018
Best Cleaner Ever
Marine 31 is by far the easiest to use and best cleaner for vinyl boat seats I've ever found. It's a little pricey, but well worth every penny.
By Ron
New Port Richey, FL
August 18, 2018
Best product on market
The only product that actually works with little effort. Awesome!!
By Cobalt Cruiser
Lake Viking, MO
August 18, 2018
Miracle Worker!
Marine 31 works miracles. We had tried numerous other highly rated products with no success. Marine 31 removed the mildew black spots from our white upholstery completely! Our boat looks brand new! Well worth the money.
By Pat Z
Dexter MI
August 17, 2018
Patricia Zamenski, Dexter MI
Bought this for my son and he loves it . He has shared or recommended this product to his friends. So glad we tried it.
By Perelco, Inc.
Montgomery, AL
August 17, 2018
Great products and will recommend to everyone
By Karen Wilson
August 17, 2018
Marine 31
We loved marine 31. It took the black mould off our boat seats and other boat surfaces.
By Alex
August 3, 2018
Hard to get out & mildew came back
We had to scrub for hours to get this red mildew stain out of our vinyl in the boat. We actually went as far as to use a power sander with the cleaner, which finally got the stains out. Even though this cleaner states it does not contain bleach, when we called up customer service about it we were specifically told to keep the cleaner off the floor and away from stitching in the seats as it would remove the color. The clothes we were wearing had large color distortions on them after done working. It also has a strong bleach-like smell. Unfortunately, the mildew came back within a few weeks -- even after using protectant. Will not be using again as it doesn't work as claimed.
Pros*Great customer service
Cons*Smells awful *Removes color from everything not specifically stated on bottle *Mildew came back *Didn't work as easy as stated on bottle - lots of scrubbing & power tools needed to be used
By Vickie
August 2, 2018
Yes it works!!
I am always skeptical when I read reviews, but this is TRULY AWESOME! My husband and I ordered this after watching a video on YouTube. We bought a pontoon that had a terrible case of mildew and spider poop spots and it removed all the mildew and spots. My husband just sprayed it on the seats and watched the mildew and spots disappear. We would HIGHLY RECOMMEND THIS PRODUCT!
ConsWe didn't buy the gallon :)
By Kim
Colton, NY
August 2, 2018
Clorox Water
This seems to be nothing more than a very expensive bottle of Clorox and water. Having said that, it did do the job, but took a whole bottle to do a 17' boat. While there is some value in getting a bleach solution that won't dissolve your seats, I certainly won't pay $25 for this product again!
By Derrick
Naples, fl
July 29, 2018
Good product but skeptical
I detail very expensive Yachts for a living, I have had a few bottles of this product and it works quite well. It is fast-acting and usually gets up the harder stains and grime. Although I am skeptical because it smells just like bleach, and stains your clothes just like bleach does, if you purchase a bottle of this once you take the top off take a smell of it and it smells just like bleach, but it's a good product overall.
ProsFast acting works great
ConsCould be just bleach in an overpriced bottle
By Andy
Ontario canada
July 28, 2018
Not bad
Saw a video on youtube and it cleaned amazingly Bought it right away and didnt work as good as I thought, you really have to scrub and apply a few times even then it doesnt get rid of all of it. My stains were quite bad too though, probably better for minor mold stains or stains that havent been there for a long time. The fumes from it really irritate the throat so use in a well ventilated place
By Lew
Glastonbury ct
July 27, 2018
Super mold removal
The best product I ever used to remove mildew Quick and easy. Spray and wait5 minutes. Unbelievable

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