Oily Film in Hot Tub? Causes and Treatments

Have you noticed a thin, oily film or scum floating on the surface of your hot tub? The good news is that this is a very common problem faced by most hot tub owners and can be easily fixed without replacing your hot tub. In general, many factors can affect the development of this oily film, but it usually forms due to the dirt, oil, makeup, sunscreen, hair products and detergent residue found on bathers when they enter the tub. Over time, these products will build up to form a thin, oily layer which is unsightly and detracts from the relaxing environment of a hot tub. In this blog post, we will address some of the best ways to treat and prevent this oily scum from forming on the surface of your hot tub.

First, let’s discuss the different types of oily scum that can form in a hot tub. The best indicator of the type of film you are experiencing is its colour. Brown scum can indicate an issue with the chemistry of your hot tub water, usually when pH levels are too high. Correcting the pH should restore the water chemistry to optimal levels and remove the scum. A green film is indicative of metals in your hot tub water, usually copper or magnesium. A hose pre-filter should therefore be used to filter the water as you fill your tub to remove metals if the green scum is a recurrent problem. Finally, a blue-green scum is a symptom of a dirty or clogged filter. All the chemical products found on bathers that we mentioned above can clog filters if they are not cleaned regularly. We recommend thoroughly cleaning your filter regularly by rinsing it with water and using a filter soak if appropriate. 

In general, one of the best ways to limit the formation of oily films is to minimize the amount of unwanted chemicals and products entering your hot tub. By showering before you enter the hot tub, you can help limit the amount of chemicals introduced to the tub. However, it can be difficult to ensure every guest is able to shower before they use the hot tub. If you do not want to ask guests to shower before they use the hot tub, you can instead focus on adjusting the water chemistry in your tub. To prevent the formation of oily films, it is important to take into consideration the levels of pH, alkalinity, total hardness and sanitizer levels. Test your water chemistry levels frequently in order to ensure that they are at the appropriate concentrations to prevent the formation of oily films.

Some simple steps to remove oily scum include using a spa skimmer to remove as much grime from the surface as possible. This should then be combined with maintaining a clean hot tub. This will help prevent the formation of oily films, reduce the need for major water chemistry adjustments and improve the longevity of your hot tub. Keeping a clean hot tub includes shocking the tub every week to help break down organic waste and emptying and refilling your hot tub every 90-100 days. This will allow you to physically wash the walls with a non-foaming cleanser to also help limit the amount of chemical build up within the tub. Floating sponges can also be added to the hot tub to help remove the oily film as it is forming. These sponges should be replaced every 30 days, where they can be squeezed out and rinsed with water to be reused again. 

Oily scum is a common problem faced by most hot tub owners. In order to prevent this common problem, it is important to ensure that you keep an eye on your water chemistry and frequently shock your hot tub water, clean your filters and remove and rinse any floating sponges. The best way to prevent the formation of oily films is to have bathers shower before they enter the hot tub. If you have additional questions or want advice on how to remove an oily film from your hot tub, call the expert team at Seaway Pools & Hot Tubs to book an appointment. We can provide a range of advice and products to help ensure that your hot tub remains clean and scum-free. Visit one of our showrooms in Markham or Newmarket for a free water chemistry test and to get all your hot tub cleaning questions answered. Contact our team today at 905-294-8030 or e-mail us at online@seawaypoolsntubs.com.