How To Clean A Fiberglass Tub – Best Option To Preserve The Finishing


Fiberglass tubs are affordable, lightweight and easy to install. While they do come with a bunch of benefits, their actual maintenance might give you a bit of a headache. Tubs do not generally require too much maintenance, as they are constantly under water and soap. But with all these, you will still have to perform a thorough cleaning procedure every now and then to ensure your unit maintains its luster and good looking appearance.

Learning how to clean a fiberglass tub is not as difficult as it may seem. Whether it tends to get dirty overtime, hard water leaves water spots, soap scum builds up or you end up with tough stains, fiberglass showers and tubs are easy to clean without too much hassle – get the right cleaning products, a spray bottle and some soft scouring pads and you will be alright. However, there are more types of cleaning out there and each of them has its own role.


How To Clean A Fiberglass Tub – Getting Rid Of Tough Stains With Baking Soda

Rubber duck in bathtub

A fiberglass bathtub can get stained pretty easily. The fiberglass surface may feel smooth and easy to clean, but the material itself can absorb dirt and leave you with unpleasant stains. Cleaning them is relatively simple though.

Soap scum tends to accumulate all the time. A classic bathroom cleaner may not necessarily handle the fiberglass surface and the finish could be affected. A bit of water and baking soda will work wonders. Mix the two ingredients until you get a relatively soft paste.

Apply the baking soda paste on the affected areas without rubbing or scrubbing. You do not want to damage the finish – it will absorb even more dirt if you do. Leave this bio clean product on the stain for two or three hours. Rinse it with warm water.

If the stain persists, you can use an acid. Do not go for anything too strong that could damage bathroom surfaces. Instead, vinegar will be excellent for this operation. Get a clean cotton cloth and soak it with vinegar. Put it on the affected area and leave it there for around an hour. Do not scrub.

Remove it, then clean the stain with a soft sponge and some warm water. A bit of soap will also help as you rub the sponge – use dishwashing soap. You can also rely on slightly stronger acids, but they could be harmful for fiberglass surfaces. Plus, you will need some protection, such as thick rubber gloves.

If the stain is still there, go for hydrogen peroxide. Whether the stain has been there for ages or it is incredibly dark, classic cleaning stuff will not help you get rid of it. You will need stronger things. Get some white clothes and put them on top of the area. They should be clean. Pour hydrogen peroxide on top of them. It will take a while, so let it soak over eight hours or so – just leave it there overnight. Rinse the area in the morning.

Last, but not least, stubborn stains can be removed with acetone – better known as nail polish remover. Get a clean white cloth, soak it with acetone and rub the stained area until it recovers its color. You can also use a paint thinner – turpentine makes a good choice. In the long run, such substances can ruin fiberglass surfaces, so use them occasionally.


Routine Cleaning For A Fiberglass Shower Or Bathtub

Routing cleaning should be performed once a week or a few times a month. It depends on how often you use the bathtub, as well as the soap you rely on. All in all, you can do it even if the bathtub looks clean – it is all about routine cleaning. You do not need to wait until stains become too deep.

Get a cleaning solution that will not ruin your bathtub. It does not have to be abrasive, but mild and liquid. For example, you can get a bucket of warm water. Add a bit of liquid detergent – stir and make sure you get a bit of foam at the top.

When it comes to choosing the right detergent, laundry detergents work wonders. Dish cleaning products are just as good – you can also rely on all purpose cleaners or even baking soda. On the other hand, scouring powders can ruin the finish of your fiberglass bathtub, so forget about them.

Once you have the mix ready, clean the whole bathtub with a soft applicator. A soft sponge will get the job done – if you use a kitchen sponge, avoid the green side. Scrub everything a few times – use regular movements. As for items to avoid, stay away from scrapers, wool stuff or scouring pads – they will scratch the fiberglass.

Let everything sit there for around an hour. Once you are done, rinse everything. Throw the remaining water in the bathtub to rinse it, then use the shower to get rid of all the soap. Leaving stuff behind will cause soap scum. Make sure you dry the bathtub – use a hand towel for it.


How To Maintain Fiberglass Bathtubs

Learning how to clean fiberglass is not difficult, but it might be challenging if you fail to perform any maintenance cleaning. Routine cleaning is one thing, while maintenance is about making everything easier and preventing hard stains. Your cleaning results will be much better in the long run.

Spraying vinegar on a fiberglass bathtub is great – you can do it twice a week or even more. Get a spray bottle, fill it with white vinegar and keep it around the bathtub for easy maintenance. Spray the surface and rinse. It will prevent nasty odors overtime, but it will also make further cleaning much easier.

Some people hang things around the bathtub – suction cups represent the most common ways to keep stuff secure. If you have such things too, make sure you remove them after using them. You can stick them on before you use the bathtub, but remove them after. The stains they leave are quite difficult to clear.

As for longterm maintenance, a bit of polishing and waxing will work wonders – you should do it a couple of times a year. You can do it yourself – get a polishing product for cars and a clean cotton cloth. Apply it everywhere, but insist around scratched parts. Once you are done, get some cream wax on and you are done. Your bathtub will look new and shiny again.

Water is also quite harmful – especially if you have hard water. Once you are done bathing or showering, wipe the area clean with a bath towel. It sounds daunting, but you should do it all the time. It takes a couple of minutes. Doing it will help you clean the things that cause soap scum. Simply put, you are less likely to get any stains further on. Turn a fan on or keep the window open after a shower or bath – the drier the bathtub, the less mildew you will have.

Last, but not least, since hard water is such a problematic issue, you can always rely on a softener. The bad news is that most homes use hard water, which will damage everything – from water using appliances to actual tubs. A water softener will remove minerals from the water – no more rust, calcium deposits, soap scum and so on. You can also add some epsom salts in the water if you take baths – they help softening water.

Frequently Asked Questions

Still not sure how to clean a fiberglass tub?


What is the best cleaner for a fiberglass tub?

Ideally, you should opt for mild and less abrasive cleaners. Baking soda and vinegar are great, but you can also use dish washing liquids. It depends on whether you need to remove a stain or you perform maintenance cleaning.


How do I get my fiberglass tub white again?

Hydrogen peroxide is a great whitener for fiberglass bathtubs. Stains can be removed with other cleaners too, yet it depends on what you are trying to do. Some cleaners should not be used on a regular basis because they can damage the finishing.


How do you clean a dirty fiberglass tub?

Cleaning a fiberglass bathtub is simple with baking soda, all purpose detergents, dish washing liquid or just a simple laundry cleaner. Make sure you opt for stuff that is not abrasive.


Can I use a magic eraser on my fiberglass tub?

A magic eraser can be great on a fiberglass, but you need caution. Do not rub too hard or you will ruin the finishing. It should be an occasional treatment only.



In the end, learning how to clean a fiberglass tub is not that difficult. It depends on whether you are performing a routine cleaning procedure or you need to get rid of stains. There are also maintenance things you can do every once in a while in order to make cleaning easier.

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