Why do bubbles and stains that are difficult to fix and clean appear on fiberglass and how to solve it

Sometimes with your purchased fiberglass hot tub, there can be additional problems. Such problems come in two forms – as in bubbles and stains. These bubbles or stains are more of an aesthetical nuisance than a serious problem. They do not affect the structural or usability integrity of the tub.

Normally these surface blemishes are caused by external factors such as sunlight, temperature differences, or extreme usage of chemicals.

Stains or blemishes appear due to irregular or no maintenance. If you do not clean the tub on a regular basis, then it will get dirty in due time. But most of the time it can happen due to calcium buildup, rust, or water contamination with external agents (soap, oils, bath bombs, and so on).

Solving the problems

Bubbles and blisters can be prevented with a couple of simple hacks. The first of them would be prevention, it helps in the future and would further give longevity to the fiberglass tub. It is advisable to keep the hot tub covered all the time when the tub is not used. This will keep the fiberglass insert away from the unwanted UV light that causes additional problems and would keep the water clean. Secondly, avoid adding more chemicals than needed or avoid mixing them, or simply using them the wrong way. Watch out for the correct water’s PH levels.

In case of a scratch or a small dent on the fiberglass lining during transportation, unloading, or inflicted during utilization, we advise you first to contact us, inform us about the situation, and then a fixing can start. First, you will receive a Fiberglass repair kit from us.

Please use the provided fiberglass repair kit by following these instructions:

1. Sand the scratched or damaged area with P 800 grit sandpaper.
2. Using the liquid from bottle no. 3, degrease the entire sanded area.
3. Mix paint (bottle no. 1) with catalyst (bottle no. 2).
4. Fill the scratch or dent with paint.
5. Let it dry for 12 hours; afterwards even out the layer of hardened paint by sanding it with P 800 grit sandpaper.
6. Sand the whole area again – start with P 800 grit sandpaper (coarsest), then continue with P 1500 and finish with P 2000 (finest). Make sure to use sandpaper sheets that have been moistened with water.
7. Using a soft cloth, polish the sanded area with polishing paste (bottle no. 4).
8. Wipe the area clean.

The mixing ratio is 2:100

2 – catalyst

100 – paint

PLEASE NOTE: the surface area, which will be repaired, must be completely dry; the temperature of the surrounding environment cannot be lower than + 16˚C

As for stains or blemishes, there is a simple hack. Most of the time a simple dish soap helps. Just fill in a bucket of warm water with a couple of squirts of liquid dish soap and then by using a sponge clean the tub. Then leave it to be for an hour and then rinse everything. Then drain and clean excessive water or remaining water droplets and the tub should be cleaned again.

The second hack that works most of the time is vinegar and baking soda mix. This mixture helps to clean all sorts of stains and can be easily made with utensils found at home. Mix both ingredients and then apply on the stains and let them sit. Then rub it with a sponge or scrub and when finished rinse it toughly and remove the remaining water. You could also use vinegar substitutes for that.

What to avoid

You should also be careful when repairing blisters or removing stains. Firstly, we advise being careful and wearing gloves in order to be safe. When removing blisters only use our given products and try to avoid damaging the tub. As for cleaning the tub, note that fiberglass is a delicate material, so avoid scrubbing it too hard, as well as metal scrubs are not advised because they can lead to scratches. Using bleach to scrub or whiten the tub is strictly forbidden because it damages the tub and discolors the tub.