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How to Fix Green Hot Tub Water

Is your hot tub suffering from green spa water? You definitely not alone as this year alone we have received over 200 calls from hot tub owners across Scotland looking for a solution to their green hot tub water.

Your hot tub water can be discoloured due to several factors, mostly resulting from a chemical imbalance which may have resulted in your hot tub turning green or with a green tint. For tackling green hot tub water, first test the water with test strips to see where the total hardness, total chlorine or bromine, pH, alkalinity, and free chlorine levels are.

Can you guess what the problem was with this hot tub?

Hot Tub Water Test Results

Answer: It obvious to what the problem is especially as our certified field water technicians are all supplied and trained with the most advanced mobile water chemistry tech, they are able to diagnose any issue within 60 seconds.

If you use a bromine system, make sure you are testing for that, too. This is how you know what to adjust. Keeping these levels in appropriate ranges will help prevent unwanted effects like horrible smells, colours, scums, and more.

Low Sanitiser Levels

While you should always maintain a proper level of spa water sanitiser, we understand life happens and spa maintenance can be put off for months. Whether you use bromine, chlorine or another sanitiser, the green water could be caused by low sanitiser levels or by not shocking your spa frequently enough.

Shocking your hot tub with chemicals allows your sanitiser to perform at peak efficiency and in best practices should be added once a week or after each spa use. You can shock your hot tub with either:

AquaSPArkle Hot Tub & Spa Rapid Shock

This is a fast dissolving granular chlorine product used for the oxidation of your spa water, eliminating bather wastes and contaminates which can be applied weekly or after heavy spa use. Available from our online store. Best Prices. Click here

AquaSPArkle Hot Tub & Spa Non-Chlorine free shock

This is a non-chlorine granular free shock that contains Potassium Peroxymonosulphate which is ideal for regular oxidisation of Hot Tub and Spa water. Non-chlorine shock is suitable for swimming pools, hot tubs and spas running on chlorine or bromine. Available from our online store. Best Prices. Click here

Low pH

Sometimes low pH can induce a green tint to your hot tub water. With an imbalance of pH, it can allow bacteria to build and discolour the water. If the pH is too low, the water is acidic and over time it can erode plastic and metal components within your hot tub resulting in avoidable hot tub maintenance charges. Do you need pH Plus? Visit our online store for Best Prices. Click here

How can you tell if my hot tub pH level is low?

Using a test strip (4-way test strips), dip one of the water testing strips into your hot tub, quickly remove it, and wait 15 seconds. After 15 seconds you can check the results on the handy colour chart that is printed on the container. Maintain pH levels within the ideal range 7.2 – 7.6. If the level is not in this range, adjust.

Low Total Alkalinity

Total Alkalinity has a direct and huge impact on pH. When TA is low, pH bounce can be impossible to control. When TA is high, pH drifts upward and makes it difficult to lower. Do you need TA Plus? Visit our online store for Best Prices. Click here

How can you tell if my hot tub Total Alkalinity level is low?

Using a test strip (4-way test strips), dip one of the water testing strips into your hot tub, quickly remove it, and wait 15 seconds. After 15 seconds you can check the results on the handy colour chart that is printed on the container. Apply when total alkalinity falls below 80mg/l (ppm) and then maintain the total alkalinity within the desired range of 80 - 150mg/l (ppm).

Keep Water Balanced

You will want to follow these guidelines and test weekly (domestic and low usage) for proper chemistry levels in your hot tub. By keeping your hot tub water and sanitiser regulated, you’ll reduce the risk of creating discoloured water.

Routine draining every 3 – 4 months is recommended (or more frequently depending on usage, bather load, etc.) to keep water as healthy as possible.

We provide a range of hot tubs services across Scotland and Northern England

Do you need your hot tub professionally cleaned?

Penguin Spas offers a variety of hot tub cleaning services to serve our customers across Scotland and Northern England. From basic hot tub cleaning to premium deep cleaning services, we have the perfect package and product to fit your needs. Our exclusive relationship with various hot tub chemical manufacturers gives us the advantage of using hot tub cleaning products that cannot be purchased at any big box retail store.

Our packages are designed to meet the needs of a wide variety of hot tub owners and holiday home business owners. Whether you are looking to bring a neglected hot tub back into service, or require a fresh fill and filter replacement, we have got the service package for you. For more information and prices for our professional hot tub cleaning services, please click here.

Expert Mobile Water Chemistry Analysis

At Penguin Spas, we provide the most advanced mobile water chemistry analysis service in Scotland where we analyse a sample of water from your hot tub or spa to diagnose any problems and advise on cleaning routines and treatments.

Whether you have a hot tub for your Holiday cottages, holiday homes or holiday park, ensuring the highest water quality is essential for the safety of your guests. Like swimming pools, strict regimes around water testing are required for your hot tub.

Penguin Spas Water Management Services, provides business owners across Scotland and Northern England expert mobile water chemistry analysis for Hot Tubs, Spas and Swim Spas where we will collect a water sample and provide immediate results using the most advanced water chemistry lab.

Our advanced innovative photometer will analyse 10 parameters simultaneously which includes: Free Chlorine, Total Chlorine, Bromine, pH, Calcium Hardness, Total Alkalinity, Cyanuric Acid, Copper, Iron and Salt.

Once the test has been complete, our system will automatically notify you of the technician’s work with a professional e-Doorhanger which summarises the activity the tech performed. A copy of the doorhanger, as well as the tech’s work history is also stored online. Click here for more information

FREE In-Store Water Testing

Penguin Hot Tubs and Swim Spas offers FREE computerised water analysis for your hot tub, spa or pool. Our state-of-the-art Waterlink Spin Touch photometer uses technology borrowed from the medical field that ensures you the most accurate results possible. A typical 10-point analysis takes less than 60 seconds and is done while you wait – coffee also provided free. Click here for further information.

Do you need expert hot tubs advice? Contact Penguin Spas on 0800 112 3886 or email and our team of hot tub experts will be more than happy to answer your questions.

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