How to Clean a Fiberglass Sink

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Fiberglass is a strengthened plastic substance that is made of merged material surrounded by glass fibers. It may seem daunting to clean one, but if done systematically, it’s easy and quick. Let’s see how to clean a fiberglass sink.

How to Clean a Fiberglass Sink

Fiberglass is used to fabricate bathroom accessories like sink, bathtubs, or any other domestic items used for holding liquids. Therefore, it is prone to getting dirty, especially for bathroom sinks, and will acquire rigid stains if not regularly cleaned.

Step #1: Use Baking Soda With Warm Water

  • Please use a soft cloth or sponge, dampen the sponge and sprinkle some baking soda over it. 
  • Scrub the sink with a sponge or cloth using moderate pressure and clean the water stains and dirt.
  • Use the other damp cloth or sponge to sweep away the baking soda from the surface. Scrub gently to keep the fiberglass finish.
  • If baking soda does not help, you may use acetone. It is safe if you use it sparingly and rub the solvent gently.

Step #2: Use a Mild-Coarse Cleanser

If getting rid of the stains is proving to be a bit troublesome, try a mild abrasive cleaner like Bon Ami, Brill-Glow, etc. 

With these, you can scrub off any stain without damaging the fiberglass. After the scrubbing, rinse the sink using warm water.

An arm with yellow gloves cleaning a bathroom sink

Step #3: Use Calcium Removers

Products like the CLR, Lime-A-way or even 5 percent of white vinegar are safe to use on fiberglass for cleaning purposes. 

Please do not use this procedure for every week wipe-down. 

Follow the steps and procedures according to the manufacturer’s guidelines and wipe it off with warm water.  

Step #4: Use Oxygen Bleach

Last but not least, if you do not get your desired results by the procedures mentioned above, using oxygen bleach sure will. 

You can either purchase or prepare oxygen bleach at home. But ensure to take necessary precautions when using oxygen bleach

  • Take hydrogen peroxide, baking soda and mix these two in equal amounts with hot water, and it is ready.
  • Now, apply it on the stains only, wait for an hour and let it work and then rinse it away.

Once you are done with the cleaning process and the sink is pleasant and shiny, you can add a graded gloss cleaner to the surface of your sink

This can increase the shiny appearance of your sink and provides a protective layer against stains.

Caution: Using too much acid and pressure while scrubbing can damage the material. 

However, you can also use solvents like acetone which is easily found in nail polish removers. 

Stay watchful when using coarse materials and techniques. They may reduce the lifecycle of fiberglass.

Here is a short video tutorial about how to clean a fiberglass or resin sink.  

Care and Maintenance

Although fiberglass is gorgeous and long-lasting, it can be pretty sensitive to acids and other abrasive cleaners and procedures. 

Over time, these get dull and develop stains. It is prone to scratches, and the more scratches, the more dirt will be trapped in them.

Therefore, you ought to keep your fiberglass sink clean and take extra care of it.

Wash your sink now and then. Do it once a day following a schedule. This will hold its shiny appearance for a long time.  

Frequently Asked Questions

How Do Fiberglass Sinks Develop Stains?

Fiberglass sinks can develop stains as they accumulate dirt and grime being with consistent usage. Especially in places with hard water, it can develop calcium and limescale spots and even rust on the surfaces.

Over years of use, it is normal for your fiberglass sink to suffer wear and tear, resulting in a dull appearance.

Close up shot of a bathroom sink being cleaned

How to Remove Scratches Out of the Fiberglass Sink?

To remove scratches from fiberglass, first, clean the sink with soap water solution. This will help to have a clear view of the scratches and their depth. Then, apply some petroleum jelly, and keep rubbing over the scratch. Petroleum jelly is also great for keeping the leather flexibility in Jordan 11 shoes.

Or add some polishing compounds to a soft cloth and rub it over the scratch in a circular motion. Wipe away the jelly with a cloth. Apply a layer of fiberglass polish to the surface unless the scratched areas will risk personal protection.


No wonder fiberglass is one of the lightest and inexpensive materials available in the market. These are durable, but you can have a hard time cleaning them, just as you clean stained glasses. That’s because it can get all scratched up if you use the wrong tools and cleaners.