We all know the dream of owning a hot tub: you come in from a long day of work and settle down for a relaxing soak with no more hassle involved than taking the cover off your spa – and perhaps pouring yourself a glass of something. But the reality is that unfortunately it sometimes involves a lot more work than this.

Here’s the truth: hot tubs can sometimes be, well, kinda gross.

But they absolutely don’t have to be, with proper cleaning, preventative maintenance and a little TLC. So, we’ve written this guide to help you figure out how to keep your hot tub in tip top shape, as well as how to combat any nasty scum, scale or stains that may occur. Read on to get all the info.

What are scum, scale and stains?

While you might think that scum, scale or stains on your hot tub are all the same thing, they’re actually quite different, with different causes – and different treatments. So, it’s worth understanding what they are, why they occur, and how you can prevent them.

All three types of hot tub dirt are caused by very similar things. Essentially, your hot tub isn’t clean enough! Either your filter isn’t working properly, or there are too many contaminants in the hot tub that you haven’t taken care of. It could be bodily residue like skin particles, or even deodorant, shampoo or make-up. It’s also possible that the pH balance of your hot tub isn’t right, the water in your area is very hard, or even that there’s metals in the water like iron or copper causing rust.

Not sure how to keep your hot tub properly clean? Check out our article to find out how often you should be cleaning your hot tub. If your preventative cleaning just isn’t cutting it and you’ve got scum, scale or stains building up in your hot tub, don’t worry – this guide can help you get your spa back to looking shiny and fresh.

Hot tub scum

So, let’s start with hot tub scum. Scum is a term for floating residue or discoloured and sometimes oily water. It can vary in severity from just a few little bits of dust or debris, right through to a nasty looking colour across the whole of your hot tub. Luckily, the nice thing about scum is that it’s relatively easy to tell what’s causing it by the colour.

If the scum is a brown colour, it’s usually due to the pH level of the water being too high. This causes iron to react with the chlorine and cause a nasty brown scum.

If you’ve got green scum – you’ve guessed it. It’s usually high copper level in the water. Either stop bringing loose coins into your hot tub with you, or you may have an imbalance of chemicals in the water.

If the scum is blue-green in colour, you’ve likely got a bigger issue. This is often caused by several different things, usually at the same time, making it much harder to deal with. Your filter may be dirty or just plain worn out, or you’ve just got a build-up of contaminants going on.

If you’ve got scum in your hot tub, you’ll want to deal with it quickly. It looks very unpleasant, but it can also irritate your skin or even cause a nasty rash, so you don’t want to leave it alone.

Hot tub scale

Scale in your hot tub is a bit easier to understand. Much like limescale or other scale in your kettle or washing machine, it’s caused by calcium, magnesium or highly alkaline water. In short, if you’re in a hard water area, you’ll generally need to take steps to soften the water in your hot tub – or you’ll end up with unsightly scale.

The real issue with scale isn’t so much that it could irritate your skin, like scum, rather that if this mineral build-up is allowed to get worse it could damage your hot tub’s filter or fixtures. So, it’s important to deal with the problem quickly. Plus, if you leave it alone for too long, it can end up staining the surfaces of your hot tub, making it even harder to clean.

Hot tub stains

So, what about stains? If you’re not cleaning your hot tub properly, eventually it will end up staining the surfaces and really starting to look unpleasant. But, even if you think you’re cleaning it properly, sometimes you may still end up with some stains.

This is because, as with scum and scale, hot tub stains can be caused by imbalances in the water that you can’t see. For example, if you’re in a hard water area, calcium or magnesium can build up and then cause staining. Or, if you’ve got iron or copper in the water, that can cause surfaces to rust. Plus, every time you get in your hot tub, you’ll be depositing contaminants like dead skin, body oils or deodorant. Over time these can build up and even stain the fiberglass of your hot tub.

How to remove these issues

Now that we’ve given you all the info on what hot tub scum, scale and stains are and why they happen, it’s time for the big question. How do you get rid of them?

The best defence is a good offense, as they say – and, as we’ve already said, the best way to combat these is to not let them occur in the first place. Regularly clean your hot tub and make sure you understand the chemicals and complex decisions involved in keeping the water clean and pH balanced.

But, even with regular cleaning, sometimes you may have to go the extra mile and remove hot tub scum, scale or stains. So, where do you start?

Removing hot tub scum

There are several different methods to remove scum for your hot tub. You could use a fine mesh skimmer to scoop up any scum that’s right on the surface, or use special oil absorbing sponges, which are specially designed to soak up contaminants from your hot tub.

If you’ve tried both of these and you’re still getting persistent scum on the water line, your best bet is just to remove a small amount of water to reduce the water level, and then get scrubbing on the scum line itself. Clean as much of the exposed shell of your hot tub as you can to remove the contaminants.

Once you’ve got to this point, if you’re still having issues with scum in your hot tub, you’ll need to take drastic action. Either clean or just completely replace the filter, or drain the water in your hot tub, clean everything and then refill it.

Removing hot tub scale

Removing scale is more straightforward than scum. With scale, all you really need to do is apply some hot tub scale remover to the area. But you need to make sure you don’t get the chemical cleaner in the water, as it’ll ruin the relaxing feeling of your spa.

For minor cases of scale, you can clean the affected shell areas above the water line, and then clean the filter to make sure the scale is removed.

If you’re dealing with a lot of scale in your hot tub, your other option is to completely drain and clean your hot tub. This is the best way to remove large amounts of hot tub scale – and you can clean your hot tub properly while you’re doing it.

Removing hot tub stains

With stains on your hot tub shell, the simplest solution is the best one we’re afraid: you’ve just got to get scrubbing. It’s worth testing the water to ensure you’re using the right product, if it’s a calcium build-up causing the staining, use a scale remover, if it’s metal content, then you want a rust remover.

Then, you just need to carry out a normal cleaning cycle of your hot tub, so shock it to kill off any bacteria, then drain and clean it – making sure you rinse and dry it thoroughly, otherwise you’ll end up with lots of cleaning products in the fresh water.

Don’t want to have to worry about all this cleaning? Got a persistent issue with scum, scale or staining in your hot tub? Get in touch with us today. Our experienced and professional team can service and deep clean your hot tub, taking the hassle and stress away. All you’ll need to do is enjoy your hot tub – and maybe pour that glass of wine.