What Causes Hot Tub Scum Lines?

Just in the same way your bath can get a dirty line around the edge, your hot tub can too. It’s a common problem that you don’t have to live with. Correct maintenance can have your hot tub shining again and keep scum lines at bay.

What Causes Hot Tub Scum Lines?

To help decide how to get rid of scum lines in your hot tub it can be helpful to understand how they develop. In most cases scum lines are accompanied by an oily film on top of the water’s surface. Common causes of these issues include:

  • Oily skin
  • Perfume
  • Lotions
  • Antiperspirant
  • Makeup

Some of us wear these types of products every day. When you relax in your hot tub the chemicals from the products wash away from your body – like a bath – and sit in and on the surface of the water. With continued use these chemicals build up around the edge of the hot tub and cause a grubby brown line to form.

However, there is another reason for scum lines. When the hot tub has excessive levels of calcium it can cause limescale. Limescale is a common occurrence in kitchens, particularly in kettles and around taps. The same happens with a hot tub; limescale coating the rim and the fixtures of your hot tub.

How Can I Get Rid of Hot Tub Scum Lines?

Correct hot tub maintenance is the best way to keep scum at bay. You can call in an expert or carry out the task yourself. Initially you will need to determine what type of scum you have.

If you test your water and it is showing excess levels of calcium it is likely limescale. To combat this, reduce the amount of calcium in your hot tub and clean the scale away with the appropriate products.

If the calcium levels in your spa are correct you can assume that the scum lines are caused by general use. In order to remove the build up of chemicals, take a cloth and add a tiny bit of your normal hot tub cleaner to it. Gently remove the scum without letting the cleaner or cloth touch the water – this can cause a foamy build up or alter the chemical balance of the water.

To avoid recurring scum lines, you can carry out the following:

  • Clean your hot tub on a regular basis
  • Make sure to clean the hot tub filter
  • Shower before using your hot tub
  • Make sure the water chemicals are correct
  • Complete a deep clean a minimum of twice per year

At the end of the day, a little TLC can keep your hot tub in fantastic condition and prevent scum lines. Thankfully scum and limescale are easy to clean and they are part and parcel of being a hot tub owner. With a few preventative measures you can keep scum at bay.

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