One really crucial aspect of hot tub maintenance that we haven’t discussed here on the BMS Spas blog yet is the twin factors of alkalinity and pH balance. So, here’s our guide on how to raise or lower alkalinity (and when you might need to), as well as a quick primer on keeping the water in your hot tub pH neutral.

Getting these two things right is really vital. Water that’s not neutral and kept in the right alkalinity range will be uncomfortable to bathe in and could even damage your hot tub’s heater or jets. So, read on to find out all the info you’ll need to keep the water in your hot tub comfortable and safe for your bathers.

What’s the difference between alkalinity and pH balance?

Before we go any further, it’s important to just spell out the difference between the alkalinity of the water in your hot tub, and its pH balance.

Alkalinity refers to the capacity of the water to neutralise acids. It’s not measured on a scale like pH, but as a measure of parts per million (ppm), much like you’ll measure the amount of sanitiser in your spa. Alkalinity is vital as it acts as a pH stabiliser, making it easier to keep the water stable. You’ll often want to get the alkalinity right before doing anything else with the water in your hot tub, as it makes everything much easier. You should be aiming for an alkalinity level between 80 and 120 ppm.

The pH level, on the other hand, refers to the balance of the water between being acid, on the one side, and basic, on the other. pH is measured on a scale from 1 to 14, with below 7 being acidic, and above 7 being basic. You want to aim for a pH measurement between 7.2 and 7.8. There are obvious problems with the water in your hot tub being too acidic, from eye and skin irritation to corrosion of hot tub parts. Water that’s too basic will make sanitiser far less effective, as well as causing scale build up on the spa surface and internal components.

So, it’s important to keep these 2 values within the right range. Plus, as we’ve already mentioned, the two will impact each other. If your alkalinity isn’t set right, you’ll find the pH fluctuates too quickly, and is very hard to get neutral. So, make sure you test the water in your spa regularly, and ensure you quickly correct any imbalance detected.

How to Raise Alkalinity in Your Hot Tub

Luckily, there are specific products on the market to help you keep the water in your hot tub balanced. To raise alkalinity, simply use an alkalinity increaser to bring that level up. Check the manufacturer’s instructions to find out the amount you’ll need to add, and slowly raise the level in your hot tub by adding the increaser.

If you’ve just refreshed the water in your spa, you’ll generally need to add some alkalinity increaser as a first principle in order to bring the level up to 80ppm+. After you’ve set the level, simply test it regularly and keep it in range by adding alkalinity increaser when required.

How to Lower Alkalinity in Your Hot Tub

The reverse problem, of having an alkalinity level that’s too high, isn’t very common in hot tub owners. However, it can happen, whether you simply added too much alkalinity increaser or for some other reason. If your alkalinity level is only slightly too high, you can simply wait a few days for it to drop back down, as it will naturally decrease over time.

However, if the level is significantly too high, you’ll need to use a pH decreaser. This will lower both the alkalinity level and the pH of your hot tub, so use it carefully and slowly to get both values back into the right range.

How to Keep the Water pH Balanced in Your Hot Tub

While your hot tub pH balance is a vital part of maintenance, it’s also fairly straightforward to get it right. Simply test the water regularly and use the required pH increaser or decreaser. If the level is within the range of 7.2 and 7.8, you’re all good! If it’s too low, add some pH increaser until it’s back in the range. If it’s too high, add some pH decreaser.

The only real hassle here is ensuring that you regularly test the water, but this will quickly become an easy habit to keep. With a bit of practice, you’ll get used to what you need to do to keep your hot balanced in terms of both pH level and alkalinity.

Need some help with your hot tub maintenance? Speak to BMS Spas. We’re the experts in all things hot tub, from maintenance to repair and removal. Get in touch today!