Hot tub maintenance is vital to ensure you and your family enjoy your spa and stay safe. The water quality needs to be monitored regularly, and there are a few other tasks that need performing frequently to keep the water crystal clear and free from bacteria or viruses that may do us harm. In this article, I will detail the basics and tell you some little tips I have found helpful.
Water chemistry for hot tub owners – Levels and tips
Most hot tub owners check the water chemistry using test strips because they are cheap and easy to use. Click here to view the current price test strips on Amazon. Follow the instructions on the packet as individual companies, instructions may vary. The strips I use only require a quick dip in the tub, the strip is then held sideways for 10 seconds, and the colour of the squares is read using the scale they provide. I have made this sound incredibly complicated, but it is not I promise!
Hot tub maintenance – Understanding the pH level of the water
The acidity of the water needs to be at the optimum level, and checking this needs to be part of your hot tub maintenance routine. If the pH level of the water drops outside of the ideal range, then the sanitiser might not work to its maximum efficiency.
Unsuitable pH can also make your skin dry and itchy. And worse of all, an unbalanced hot tub can smell bad! (okay, not the worst thing ever, but still unpleasant) The ideal pH is between 7.4 and 7.6. If you are using bromine to sanitise your hot tub, then try and stay to the lower end of that range (7.4)
On your testing strips, other measures may be significant. I say may because I generally ignore them, unless I notice a problem. For example, calcium levels need to be maintained at 150 – 300 ppm. If they are higher than this, it can cause cloudy water and potentially limescale in your heater.
However, as you will be changing the water at regular intervals, this is less of a worry unless your mains water has a high calcium level to start with. If this is the case, you can use trisodium phosphate to reduce levels.
All I know is I have never had to alter this! Another measurement on your strip is Cyanuric Acid which helps stabilise chlorine when it is in direct sunlight. Cyanuric acid is vital if your hot tub is chlorine sanitised and you do not have a lid, but otherwise ignore this.
Maintaining sanitiser levels (Chlorine / Bromine)
This is by far the most critical measurement you will be taking if you are lucky enough to own a hot tub or spa. Keeping your sanitiser level correct will mean your hot tub is safe. The pH level drifts relatively slowly, but your sanitiser can drop from perfect to zero very quickly depending on how you use your spa.
Chlorine is most susceptible to this wild fluctuation because after chlorine reacts with bacteria or viruses it chemically changes, which results in it being ineffective. Chlorine is also broken down in hot water, so even if the hot tub is sterile, chlorine levels will fall over time. If the chlorine level drops to zero, then your hot tub turns from a little piece of paradise to a bacterial soup. Click here to read about hot tub diseases and infections – not for the faint-hearted!!
So how do we avoid this?
Firstly, you will have to perform a ‘shock’ once a week, and I’ll explain that in another paragraph below. The second thing you will need to do is test the water frequently to monitor the chlorine levels. When I was using Chlorine (I now use bromine – click here to read an article detailing why I changed) I would check the tub in the morning while the kettle was boiling for that magic first cup of tea of the day.
I would generally need to add about a teaspoon of chlorine granules. After my wife and I had used the hot tub in the evening, I would add about the same amount of chlorine again. I knew by trial and error that the chlorine level would stay in the ideal range of 3-5 ppm.
The ideal bromine level is 2-5ppm if your primary sanitiser is bromine alone. If you have an ozone sanitiser and/or are using a mineral sanitiser, the bromine level can be kept lower at 1-2ppm. But please follow the manufacturers’ recommendation on this, as the exact level may be different depending on the quality of the ozone generator or mineral level. (See this article if you are unsure which sanitiser might be best for your hot tub)
So, now the water chemistry is sorted, that’s it? Good to go?
Yes and no. You are good to go for about a week and then more action is required in the form of shocking the hot tub.
In chlorine sanitised hot tubs, shocking the tub involves adding more chlorine to a level of 10ppm for a minimum of 4 hours. This removes all the nasties in the water. If the water was getting a little cloudy, then this process should get the water back to crystal clear.
You may want to shock more often if you have had a party and many people used the hot tub, or if you are struggling to maintain the chlorine level in the optimum range. If the latter is the case, this is caused by bacteria levels being too high.
Bromine sanitised hot tubs require a non-chlorine shock. Like the chlorine shock, this breaks down organic waste and contaminants. The shock also re-activates the bromine which is why you need to add fewer chemicals to a bromine sanitised hot tub.
Before you shock your hot tub, remove the filters and rinse them under a fast running hose to remove any macro dirt and fluff. (Inflatable hot tub owners need to clean the filters after each use or every three days as a minimum. (Click here to read another article detailing if an inflatable hot tub is right for you!)
So, now the water chemistry and the shocking is completed – good to go?
Yes – for about a month! Then you need to remove the filters and clean with a specialist filter cleaner or filter soak. Top Tip: I recommend you have two filters, so when one is being cleaned you can swap the filters over. This also gives the filter time to dry which will kill anything left on them after the deep clean.
Okay, we have sorted the chemistry, washed the filters, applied the shock and given the filter a monthly deep clean. After all this work, we need a soak!
But there is more we need to do…. Really I hear you say!!!
Hot tub maintenance – the last bit!
Every three months or so you should change the water. There is a debate about how often this is needed and there is no exact science to this as it depends on how often you use the hot tub and what the levels of water contamination are. I have left it longer (like nearly six months!), and the water was still crystal clear and safe.
Now my children use the hot tub more; I change the water every three to four months. I even have the date written on the calendar, so I do not forget! When the hot tub is drained, I use a hot tub pipe cleaner to make sure the hidden areas of the hot tub are clean and do not contaminate my fresh water.
I hope you found this article helpful and now understand the basics of hot tub maintenance!! – Feel free to comment below or contact me directly in the contact section of the site. I usually check the mailbox every couple of days. Remember to sign up for our newsletter!!
Hey, why not check out our article on Bluetooth waterproof speakers for your hot tub. Is it time to start mixing bubbles and music?