Hot Topic: Soap Scum and Hard Water Stains on Your Fiberglass Shower?

fiberglass shower

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The biggest trend in modern bathrooms over the past decade or so has been the fiberglass shower. It's a beautiful, elegant trend... when it's clean. However, hiding soap scum and hard water stains was a bit easier with curtains. So, if you're a homeowner struggling to deal with scummy stains, see what these DIYers have for advice.

Original Post: How to Remove Soap Scum and Hard Water Stains from Fiberglass Shower?

squale Member

I have all fiberglass showers and tubs in my house. Unfortunately, I have hard water, and this makes a lot of mineral and soap scum buildup all over the shower.

Does anybody know of a product that I can spray or wipe on, leave it on for a few minutes, then just wipe away the soap scum? Right now I use Ajax and other general-purpose household cleaners, and I have to sit there and scrub and scrub and scrub for a long time until I get the soap scum off, and I still can't even get it all off then. This stuff is very persistent!!!

Also, is there something I should spray on the shower/tub after I use it every time to prevent the soap scum from building up?


Highlights from the Thread

twelvepole Member

The key to keeping shower scum and mineral deposits at a minimum is to wipe shower after each use with squeegie or chamois. Some claim that using a daily shower mist product after each shower does a good job and saves extra work when it comes to the recommended weekly shower cleaning.

Abrasives tend to scratch and roughen up gel coat on fiberglass, making surface more attractive to mineral deposits and scum. Products like Ajax are not recommended for fiberglass. Use only nonabrasive cleaners.

There are many cleaning products available in the cleaning aisles that are good scum and mineral deposit removers if given the time to dissolve them. Most people do not give their cleaning products time to do their jobs. Repeat applications may be necessary for severe buildup. Spraying and immediately wiping tends not to be effective where there are scum and minerals.

A popular product mentioned in forums for mineral deposit removal is CLR (calcium, lime, and rust remover). A couple powdered cleansers that are safe for fiberglass and excellent rust, mineral, and scum removers are BarKeeper's Friend & Zud. Allow cleaner & water paste to set to dissolve minerals and scum. Rub off with damp cloth. Repeat applications may be necessary for severe buildup. For a little extra action that will not harm fiberglass, use the pink & white ScotchBrite pad to facilitate removal.

Once you get the showers and tubs clean, wax with auto wax to provide sheeting action to minimize water drops that adhere to shower walls. Avoid wax on tub and shower floors because they will be slippery and possibly cause a fall.

Water drops that cling to shower walls dry, leaving a ledge of mineral deposits. Each time you shower additional drops will find their way to the mineral deposit and cling there. With every shower, the mineral ledge grows larger, attracting more drops, minerals, and scum. Thus, it is important to provide sheeting action and wipe showers down after each use. Then, with the weekly cleaning and maintaining the wax, mineral deposits and scum tend not to be a problem or compound cleaning problems. For water with large amounts of minerals, a water filter/softener system is recommended.

Docduck Member

The best way to remove mineral build ups is to use a acidic pH cleaner. CLR should work great. Read the back very carefully. In several applications it either recommends a short dwell time...or a immediate removal after applying.

Annette Member

I think the WAX would work and probably stay on even longer, or that Rain-X stuff for car windshields, or the stuff they make to spray on shower walls after showering-- all keep the walls slick so that the gunk won't stick.

Debbie Long Member

Another idea that I use- dryer fabric sheets. You wet the sheet, rub it over the walls, and rinse. It not only removes the soap scum, but also the fabric softener in it repels the water beads, thus preventing scum buildup. I use it about once every two weeks, and it seems to keep the scum level down.

Read more tips and tricks for dealing with scummy soap on fiberglass showers here: //