How to Properly Clean Your Hot Tub Cover

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Proper maintenance will help your hot tub cover last many years. Knowing which products to use, and which to avoid, can be the difference between a good return on your investment or a recurring expense. Here, I will walk you through the steps and teach you what you need to know to get the best longevity possible from your spa cover.

What You’ll Need

To properly clean your cover, you will need:

  1. A gentle non-abrasive cleaner
  2. A sponge
  3. An oil free protectant


The most common cause of cover fading, cracking and deterioration is the use of damaging products. Vinyl is similar to leather, it requires a gentle cleanser. Avoid using products that contain:

  • Alcohol
  • Bleach
  • Detergent
  • Dish Soap
  • Oil


Abrasive cleaners strip the clear top coating of vinyl causing it to fade, crack and eventually require replacement.

Oil based “protectants” (including a leading automotive line containing silicone oil) are extremely damaging because they amplify sun rays, essentially cooking your hot tub cover.

Cover Cleaning

The first step to cleaning your cover is to wet it down with a garden hose. This will help to loosen the dirt and allow you to wipe down the surface with less friction.

Spa cover cleaning 018 2

After most of the water has run off, apply a non-abrasive cleaner to your cloth or sponge and start wiping. Be sure to rinse your sponge regularly, re-applying cleaner each time, otherwise you will just smear the dirt around.

Don’t forget the apron or underside!

Maintaining the integrity of the vinyl’s topcoat, and protecting against UV damage are keys to keeping it looking and performing like new.” Says Garth, Spa Cover Expert at

For especially tough areas like caked on dirt or bird droppings, try the following:

    1. Spray on non-abrasive cleaner
    2. Let soak 1-3 minutes
    3. Wipe away
    4. Repeat if necessary

Spa cover cleaning 033

Note: Tree sap and pitch can be easily removed by rubbing in a little margarine or olive oil to the effected area.


Once the sap is removed, clean this area to remove any remaining oily residue.

Moss & Mildew

During the winter, you may notice moss or mildew starting to grow on your cover.

My spa cover had moss growing in the zipper and stitching. With a little CleanAll Spray and the rough side of a sponge, I was able to clean all of it off in just a few minutes.


After cleaning off moss or mildew, remember to reapply a liberal amount of 303 Protectant. This acts as a sunscreen for your cover, to keep the vinyl from fading or cracking.

Dealing with Mildew Inside the Vinyl Jacket (Indicated if odor is a problem)

  • Unzip the jacket and carefully remove the foam cores.
  • Clean the inside of the jacket with a non abrasive and a soft brush.
  • Clean the core’s plastic vapor barrier.
  • Spray surfaces with garden hose.
  • Towel-dry all surfaces, and allow for additional air-dry time of the jacket.
  • Sunlight exposure for an hour or two helps rid residual mildew from inside the jacket.
  • Foam core should be kept in the shade while drying.
  • Carefully reassemble when dry.
  • Note: If foam core is rotten and waterlogged, cover requires replacement.

Prolonging Cover Life

Another major contributor to cover failure is damage caused by over-chlorination, excessive ozone contact, or imbalanced water chemistry.


Imbalanced water chemistry can cause vinyl puffiness, stitching disintegration and bleaching of the cover’s underside.


Prevent underside bleaching by testing & balancing your water weekly.

    • Alkalinity between 80-120
    • pH between 7.2-7.8
    • Chlorine between 1.5-3 or Bromine 3-5
    • Prolong cover life by using a ThermoFloat Blanket
    • Remove cover when adding spa shock and other chemicals.

Cleaning your cover once every 1-3 months will keep it moisturized and looking fabulous for years. Even an older cover can benefit from a thorough cleaning and protectant treatment.

Do you have any questions about cover cleaning or hot tub maintenance? Post your question below!


  1. Hi Bill, Great question! Re-stitching will require an industrial sewing machine with heavy duty triple-ply polyester thread. The vinyl jacket is removable via zippers in the fold area. So, you should be able to bring the jacket in to your local alterations company to be repaired with the thread type mentioned above. I hope this helps! Please let me know if you have any additional questions. Thank you, Kaisa The Spa Depot

    Liked by 1 person

  2. Helpful article. The only disagreement I have is with using the ThermoFloat blanket. The hot tub chemicals cause the ThermoFloat blanket to deteriorate causing little bits of plastic to flake off. Some of these floating plastic bits clogged up my flow valve and cost me a bit to have it replaced.

    Liked by 1 person

  3. Hi Tony, Thank you for your comment! A deteriorated ThermoFloat Blanket is indicative of imbalanced water chemistry. Most commonly this is caused by pH that is too low, but could also be due to excessive ozone, alkalinity imbalance or too much sanitizer (over chlorination/brominating). Your cover could suffer the same fate over time. If you would like, we can help you figure out what’s awry. Please feel free to give us a call (800) 823-3638 and ask for Mark in Technical Support. Thank you, Kaisa The Spa Depot

    Liked by 1 person

  4. Hi Luigi, Great question. Yes, you can remove most stains from the cover underside. To do so, wet stained area with Spa System Flush and let soak for 4 hours or overnight, then wipe with a rag. This will remove 99% of stains without harming the vinyl like chlorine will. Please let me know if you have any other questions. I am happy to help! Thanks, Kaisa The Spa Depot

    Liked by 1 person

  5. We have a slimey scum build up on the inside of our spa cover, which was brand new in May 2013, and use the Clearwater Blue system from SpaDepot to maintain our spa water. What is this yucky deposit and how may we prevent it??

    Liked by 1 person

  6. Hi Randy and Donna, The build up is caused by improperly balanced, or improperly treated spa water. The two most important things in your sanitizing system are the Cleanwater Blue itself, and the Oxy Spa shock. Make sure you add the proper amount of Cleanwater Blue per the directions, and be sure to use two tablespoons of shock after each use. You do need to shock the tub at least once a week even if you do not use it. Additionally, 303 Protectant not only works great for the outside of your cover, it helps prevent build up on the underside of the cover: Thank you, Mark The Spa Depot

    Liked by 1 person

  7. I can”t seem to get that “funky” odor from my hot tub cover. I scrubbed it inside and out with bleach and water, let it dry, put Styrofoam back and I think it is still the cause of a foul smell in the water. And, should underside of cover make contact with the water? Thank you, Mark

    Liked by 1 person

  8. Hello Mark, thank you for your comment. Is the hot tub cover water-logged? You can tell if you unzip the vinyl and feel or see water trapped in the plastic wrapping around the foam. A water logged hot tub cover is usually very heavy. If this is the case, water is becoming stagnant inside the plastic wrap and causing the odor. Generally the cover should not make contact with the water. Thank you, Kaisa The Spa Depot

    Liked by 1 person

  9. Hey Thanks for the post Any recommanded product please? This will help me a lot to make my Cover as a new one Thanks Best regards Patrick

    Liked by 1 person

  10. Hi Karisa, I”ve got the same problem as Mark. I just cleaned the cover this weekend and did all the recomended steps but the cover still has a strong mildew smell. The foam is not water logged but it is covered by plastic wrap which I did not remove because I didn”t think I”d get it back on right. But the smell is clearly coming from the cover material so do I just live with it or should I replace the thing or do I have another option. Any advise would be helpful. Thanks

    Liked by 1 person

  11. Hi Paul, Thank you for your comment. If you have cleaned the inside of the cover thoroughly and still notice the mildew odor, it is likely coming from inside the foam cores. This happens when moisture has penetrated the plastic and starts to grow bacteria and mildew. If your cover is in overall good condition, a way to reduce the odor is to make a small slice into the plastic around the foam and allow any trapped water to drain. Once it is thoroughly drained, patch the slice with clear packing tape, then go around and tape up any areas where water might be able to penetrate into the foam. If the cover is in bad shape, it may be worth replacing. I would recommend getting a double wrapped core on your next cover. Adding the additional water barrier really helps with longevity, odor and energy savings. Please let me know if you have any additional questions! Thank you, Kaisa The Spa Depot

    Liked by 1 person

  12. Hi Barbara, thank you for the question. Yes, these products should help to eliminate the chlorine odor. Please let me know if there is anything else I can assist you with. Thank you, Kaisa The Spa Depot

    Liked by 1 person

  13. Liked your article,but you didn”t specify what to use as a protectant to revitlilize the cover. Would a vinyl spray used on car interior work?Thanks Larry

    Liked by 1 person

  14. Hello Kaisa, I just found you and now I am a follower. Read some of Your advise on spa cover maintainence for other people. Thank You! 303 cleaner I will track some down hopefully Wal Mart. What about an Armor All protecting after the cleanings? Thanks you can email me as well as blog it.

    Liked by 1 person

  15. Hi Scott, Thank you for your comment. Any silicone based products or products containing oils are not recommended for spa cover use, as they can lead to rapid deterioration of the vinyl. 303 Protectant is safe to use because it is oil free. Please let me know if you have any additional questions. Thank you, Kaisa The Spa Depot

    Liked by 1 person

  16. I purchased a new cover for my hot tub and we have been using it for about one month. Today we went to use the hot tub; the underside of the cover has a slime feeling. The test strips show the water levels are good. Do you have any ideas? Thanks,

    Liked by 1 person

  17. Hi Diane, Great question! Typically a slime feeling on the underside of your hot tub cover would be the result of an imbalance in the water. I would recommend a couple of things. If your filter is over a year old it should be replaced, if not I suggest a thorough cleaning. I would also recommend draining and refilling your tub if your water has been in the spa for longer than 4 months. You will also want to thoroughly clean your cover with a non abrasive cleaner such as CleanAll Spray in order to remove the current film: Please feel free to give us a call if this problem persists, we are happy to help! (800)-823-3638 M-F 8-5pm Pacific Thanks, Bonni The Spa Depot

    Liked by 1 person

  18. Just opened the hot tub cover after 4 month, now I have mildew spots all over. How can I clean it ? Thank you Regina

    Liked by 1 person

  19. Hi Regina, Thank you for your question! To remove the mildew spots from your cover I would recommend removing your cover to a safe dry place and using a little Spa System Flush on a damp rag to spot clean. After your cover has had some time to dry out, apply 303 Protectant all over. Also, if your hot tub is not going to be in use for long periods of time I would recommend either draining it, or continuing to maintain your spa water weekly as well as removing the cover every so often to allow it some relief from the moisture. This will help prevent mildew in the future. Please let me know if you have any further questions! Thanks, Bonni The Spa Depot

    Liked by 1 person

  20. HI –
    I have clearly used something bad on one area of the cover and it shows some cracks and is absorbing rain. Anyway for me to reseal my blunder?

    Liked by 1 person

  21. Hi Dee,
    If the damaged area on your cover is small I would recommend using a vinyl patch kit:—Type-B-P9343C57.aspx
    Although, if the cracks are covering a larger area and absorbing water, it may be time to replace you cover.
    If you need further assistance please feel free to give us a call at your convenience (800) 823-3638 M-F 8am-5pm Pacific.

    Liked by 1 person

  22. I had to take my cover off because it was full of water. On the underside of my hot tub cover the vinyl is dry andcracks when I move it. What can I use to keep it from cracking

    Liked by 1 person

  23. i have paint over spray and need to remove the paint. i think it is water based. what can i use to clean the paint?

    Liked by 1 person

  24. Hi Ernie,
    I would try using a Mr. Clean Magic Eraser on a small part of the cover as a test. Afterward, apply 303 Protectant after you have removed the paint from the vinyl.
    Chemical paint removers will damage the vinyl.
    I hope this is helpful. Please let me know if there is anything else I can assist you with.
    Thank you,

    Liked by 1 person

  25. Hi Hody,
    What you’re describing sounds like the vinyl may be deteriorating due to chemical damage. This is caused when imbalanced water chemistry or an abrasive chemical comes in contact with the cover, eating away the protective top coat and allowing the plasticizers in the vinyl to escape.
    While there is no way to repair the damage, you can slow the disintegration process by using 303 Protectant.
    Please let me know if you have any additional questions.
    Thank you,

    Liked by 1 person

  26. We just got a new hot tub and I wore a bathing suit in it and the dye from the suit came off and has stained the beautiful hot tub vinyl on the inside with red! 😦 Does anyone know what can clean this? We have tried magic eraser, bleach, vinegar,

    Liked by 1 person

  27. anyone know how to remove tree pollen (maple)from the top surface of a vinyl hot tub cover? I tried the stuff at a big n famous hot tub place in town, not much good. Then, tried liquid spic n span, little better, then top job, about the same outcome. Any help be appreciated very much, it’s yellowish in color, very stubborn!

    Liked by 1 person

  28. Hi,
    I live in Scotland and we have a brown leather lid on our hot tub. Is there any way to stain or change the colour of our lid to grey/black? And get the shine back again?
    Thank you

    Liked by 1 person

  29. Hi Isla,
    We would not recommend dying the vinyl jacket of your spa cover, since the dyes could stain the hot tub shell or water. To get the shine back, use 303 Aerospace protectant. It really works wonders on dull old vinyl.

    Liked by 1 person

  30. Nice Blog post!! The content you have shared is very insightful. Thank you so much for sharing such valuable information with us..


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