How to Clean a Stained Fiberglass Tub

Fiberglass bathtubs are popular for many and various reasons. However, they readily accumulate buildups of dirt and minerals from the water. Hard water is particularly notorious for staining fiberglass tubs. Water stains fiberglass by depositing dissolved minerals onto the fiberglass, which appear as stains when the minerals begin to solidify. The dissolved minerals harden onto the surface of the fiberglass when the water dries, and then they begin to build up deposits as they combine with and trap grime, oils, dirt and soap scum. The one thing that everyone can agree about when it comes to fiberglass bathtubs is that they can be challenging to clean.

Difficulty: Moderate

Instructions

Things You'll Need:

• Plastic (not metal) bucket, pail or large bowl
• Plastic spray bottle
• Soft washcloths and bath towels
• Soft scrub brush or non-abrasive scrubber
• Toothbrush
• Salt
• White distilled vinegar
• Baking soda
• Lemon juice
• Car wax

1. 
    

   Pour distilled white vinegar into a plastic bucket, pail, or large glass bowl. Dip washcloths into the vinegar and apply them to the stained areas of your fiberglass bathtub. Let them set for about 15 minutes or so. The acetic acid in the vinegar will soften the built up deposits, and begin to loosen the stains.

2. 
    

   Take the cloths out of the bathtub and use a scrub brush or soft, non-abrasive scrubber on the stains. Use an old toothbrush for any areas that are difficult to clean with a brush or scrubber. Then rinse the tub very well with hot, clean water. Dry it completely with a clean towel.

3. 
    

   Use lemon juice on any stains that might still remain by repeating Step 1 and Step 2 with the juice instead of vinegar.

4. 
    

   Combine 1/4-cup of salt with 1/4-cup of baking soda, if even the lemon juice didn't remove all the stains. Add enough warm water to the dry mixture to form a stiff paste, smear it onto the stains and scrub with the brush or scrubber. Use the toothbrush for hard to reach areas. The baking soda will lighten the stain, and the salt will provide a harmless but effective abrasive. Rinse very well with hot water. You may have to rinse two or three times, as baking soda is heavier than water and will tend to collect on the bottom of the tub. Dry the bathtub thoroughly.

5. 
    

   Make sure that it is completely clean and dry, and then apply car wax according to the directions on the package.

6. 
    

   Allow the car wax to dry, and then use a clean, dry, soft cloth to remove the dried wax. Use another clean cloth to buff the tub to a nice shine. Waxing your fiberglass tub will help enormously with preventing future stain buildups, and works very well for all of your tile, also.

7. 
    

   Combine vinegar and water of equal portions in a spray bottle for daily maintenance of your tub and tile. Spray it onto the surfaces, rinse well with hot water and wipe dry with a clean, dry cloth.

Tips & Warnings

• Scrubbing soap scum with shampoo will break down the oils in it and allow you to easily rinse the nasty stuff away.
• Harsh abrasive cleaners can easily cause damage to the finish of your fiberglass tub, so never use them. Not all commercially prepared cleaning products are formulated with fiberglass in mind. If you use them, be safe and test the product in question on a tiny inconspicuous area of your bathtub.

Resources

• Helpful Forum for Bathtub Concerns