How to Remove Fiberglass Pool Stains

Fiberglass pools generally are easier and cheaper to maintain than other types of pools. They rarely suffer from pool stains when properly maintained and managed. They also need fewer chemicals and low amounts of electricity. Another attraction of fiberglass pools is that they have smooth surfaces that won't cut or scratch swimmers. 

Discoloration that is similar to bathroom rings, however, can appear on the waterline because of suntan creams, body oils and metals in the pool chemicals. Rust could also build up in a fiberglass pool, and is caused by chemicals and mineral deposits. Rust stains are a bit trickier, but with the right tools and equipment can be removed easily.

Check your owner's manual for instructions on how to remove bathroom rings and other forms of stains from your pool or call the manufacturer directly for tips and procedures. For alternative and supplemental solutions follow the tips below:

Step 1 - Remove Light Bathroom Ring Stains

Apply commercial products like Off the Wall, Jack's Magic Blue Stuff, and pool tile cleaners on light bathroom rings found around the pool.  They are known to effectively remove bathroom ring type stains. You can also apply vinyl cleaner or non-abrasive tile that were not originally designed for pool use.

Another way of removing light stains is to scrub the affected area with a sponge, soap and warm water. You can also use liquid dish detergent as an alternative to soap.

Step 2 - Remove Heavy Bathroom Ring Stains

Put oxalic acid in the water to remove heavy bathroom ring stains. The water may appear cloudy for a few days following treatment. Run the pool filter to clear the cloudy water and then pour chlorine. Follow manufacturer's specifications as to the amount of chlorine for your size pool. Make sure that the pH balance of the water is 7.5 when the pool filter is in use.

Mr. Clean Magic Eraser is another effective bathroom ring product. Scrub the liquid solution into the affected area until it clears up. The solution is gentle and will not damage the surface. Do not use commercial type abrasive brushes or cleaners when removing stains, as this may damage your pool.

Step 3 - Removing Rust

For rust, apply a Vitamin C tablet directly to the stain until it clears up. If the stain is caused by metal, the rust would normally dissolve quickly. Use a soft-bristled brush to remove excess rust. When you have rust infection spread out across the pool, put ascorbic acid powder to your pool filter. Follow manufacturer's specification for optimal results.

Another way of dissolving rust is to rub chlorine tablets on the affected areas. Use a soft bristled brush to remove stubborn and excess stains.

Step 4 - Stain and Rust Prevention

For prevention, remove all foreign metal objects from the pool. Follow manufacturer's specifications when adding or putting chemicals in the water. Also add metal treatment when you're adding water to the pool. Regularly check your pool's pH, making sure that it's always at ideal levels.

Pool stains need to be cleared right away, because they become stubborn and hard to remove when left unattended for a long time. It's recommended to use household products first such as soap and water when removing stains, as they contain light chemicals that are kind to pool surfaces.