Hot Tub Maintenance Guide

Looking after your Spa/Hot Tub

The circulation/filtration system and your chemical dosing regime.

When starting up your spa for the first time or when refilling after it has been emptied for a period, it is strongly advised that you shock dose the fresh water. This is a simple procedure and raised the chlorine levels to kill off any bugs and germs in the water. The free available chlorine level should be take to either 25mg/l (ppm) for a minimum of two hours, or 50gm/l (ppm) for a minimum of one hour. Always check on the label. While the spa is being chlorinated to high levels, the water must be allowed to flow to all parts of the system, regularly monitoring the chlorine residual to ensure that it does not fall below the specified level at any time. Where an air blower is installed, it should not be run for the first 15 minutes to minimise the formation of aerosols (fine spa water mist).

During shock chlorination, the pH should be maintained within the range of 7.2 – 7.6 in order to ensure maximum effectiveness of the disinfection process.

It's important that after the one or two hour shock treatment period, the spa should be drained, thoroughly flushed and refilled with fresh tap water, and run at normal disinfection levels. If this is not possible for practical reasons, leave the spa with the cover off and the chlorine level will fall naturally. The spa should then be drained, thoroughly flushed and refilled with fresh tap water.

The quality of mains tap water varies from area to area; you may even have a non-mains source such as spring or well water. As a result, different levels of pH, total alkalinity, calcium hardness and mineral content will be found in the water that you fill your spa with. In hard water areas of the UK or if there is a high mineral content, it is strongly advised that you add a spa anti-scale directly to the spa water when filling and also every time it is topped up or refilled after periodic draining. This should help to minimise scale formation and staining of the spa surfaces.

The filtration system consists of a circulation pump and filter; the pump moves the water through the system. The filter removes small particles, which if left could turn the water cloudy. Periodically the spa filer will require cleaning. This will depend on how often the spa is used. The cartridge can also be cleaned with a spa cartridge filter liquid bought from a pool shop. This will remove small minerals and greasy deposits that have been trapped in the filter which if left, will impair the filter's performance and cause the water to become cloudy.

Your spa water should always look clear, brought and inviting. If, for any reason, it doesn't, it can usually be brought back to life with a spa water clarifier. This insists the efficient removal of small suspended particles, which in sufficient quantity will cloud the water.

When treating the spa water when you have just filled your spa it should look good enough to drink. This doesn't mean that you don't need to add any chemicals. The simple reason being that when you get into your spa, you carry with you numerous small particles, including bacteria. Bacteria are so small they're invisible to the naked eye, but that doesn't mean that they can be ignored.

Living organisms such as bacteria need, as we do, food and water to survive and flourish. The water is already present, the food is usually in the form of organic material and because you consist mainly of organic matter, each time you climb into the spa you introduce this in the form of skin particles which are covered in bacteria, along with other nutrients. Your should therefore ALWAYS treat the water and kill off these bacteria.

The Spa Temperature

Most modern spas and Hot tubs have a built-in temperature gauge but if one is not supplied, invest in a good quality thermometer. The maximum temperature should be 40°c. Most people find a temperature of 37°C to be more relaxing; temperatures above this tend to feel a little uncomfortable. Due to the higher temperatures your spa operates at, you may occasionally get a little scale formation particularly if you are in a hard water area, but again this can easily be prevented or removed instantly by adding an anti-scale or spa de-scaler directly into the spa water.

Keep your Spa/hot tub clean

Just like your bath, grease and body fats can collect along the waterline which not only looks unsightly but can prove to be a breeding ground for bacteria. It is good practice to clean this off regularly using a surface cleaner. This is specially formulated to clean away body fats and grease easily and quickly, and can also be used to clean the spa interior when it is periodically drained before it is refilled with fresh tap water.

Draining your Spa

Although the water is constantly being re-circulated, filtered and sanitised, micro-organisms capable of withstanding normal sanitiser levels can survive out of reach in the circulation system. On rare but a few occasions, these can give arise to serious infective illnesses. For this reason, it is a good idea to periodically shock treat the spa water, then drain the spa and refill with fresh tap water.The frequency of draining will depend on usage; if your spa is just for family use, it should ideally be drained and refilled every two months and at least every three months.

To help combat anything that might be harmful to health, shock the spa water prior to draining using a good quality spa shock granule. In this context, shock dosing means raising the chlorine level well beyond normal concentrations.

Foaming spa water

The water in your spa is circulated very quickly; air is also introduced regularly and, together with the build up of body oils, foam can be created on the waters surface. While this will cause little harm it's not attractive and needs to be removed. You can purchase anti-foam liquid which is specially designed to remove this unsightly foam, and if you use it on a weekly basis, this will ensure that foam is not a problem.

Having problems with your spa? Check out our hot tub troubleshooting guide