Non Chlorine Shock (Potassium monopersulfate) also known as MPS is a chemical that provides a lot of benefit to your hot tub water and maintenance routine but also a product that very few hot tubbers understand or have used. In this article, we aim to answer some of the key questions around this chemical including "What does Non Chlorine shock do?", "Does it replace Chlorine or Bromine?" and "How often should I use it?".

What is Non Chlorine Shock?

Non Chlorine Shock is a powerful, odourless oxidising agent, which essentially means it works to eliminate contaminents in hot tub water. Oxidation is different to sanitisation. Oxidation is the breaking down of the oils and organics in your water whereas sanitisation is the killing of bacteria. Sanitisation is performed by effective sanitisers like Chlorine or Bromine. Note that while sanitisers can also oxidise, their effectiveness in both actions is reduced so you tend to use lots more sanitiser to perform both. Oxidation is performed very effectively by Non Chlorine Shock (Potassium monopersulfate) and this is why it offers great benefits to your hot tub experience. Non Chlorine Shock works with all sanitisers but does not replace them as it is not a sanitiser! 

What Are The Benefits of Using Non Chlorine Shock?

  1. Improved Sanitiser Efficiency. By using an effective oxidiser like Non Chlorine Shock alongside your sanitiser, you free up your sanitiser to do what it is good at - kill bacteria! This results in less sanitiser being used in your hot tub. 

  2. Fast and effective removal of oils and more. Non Chlorine Shock will oxidise oils such as body oils, lotions, deodorant, dead skin cells, sweat, detergents or leaves from your hot tub water, helping to prevent or reduce foaming and to reduce strain on your hot tub filters. This can also reduce reliance on chemicals that should be used sparingly such as Anti-Foam.

  3. Help water clarity. For many of the reasons outlined in point 2, Non Chlorine Shock can help improve water clarity fast. If you have milky or cloudy hot tub water but your chlorine levels, PH and alkalinity are ok then Non Chlorine Shock will oxidise the products causing this and help restore your water to crystal clear. 

  4. Reduce the need to super chlorinate. Super chlorination is a good way to oxidise but by raising the chlorine level super high, you are risking bleaching and will potentially make the hot tub unusable for a period of time due to the strong smell/high chlorine level. 

  5. Break down Chloramines. Sanitiser reacts with bather pollutants such as perspiration or dead skin, and produces a less effective chemical compound called chloramines (used up chlorine) which needs to be broken down. Chloramines have a strong chlorine odour that is often mistaken for too much chlorine, they can make the water appear cloudy and also sting your eyes. Non Chlorine Shock will effectivley oxidise this used up chlorine from the water, improving your bathing experience massivley.

  6. Re-generating spent bromine. Unlike Chlorine which turns into Chloramines once spent, Bromine can be regenerated. Using Non Chlorine Shock in a hot tub running on Bromine will oxidise the bromide ions (spent bromine) and form new bromine, this boosts the bromine level.

When and How To Use Non Chlorine Shock 

Non Chlorine Shock is a powder that comes in many forms which we will outline below. We recommend adding Non Chlorine Shock weekly alongside your existing hot tub maintenance routine but in some situations such as severe foaming or cloudy water, extra dosing may be required. You can click through to each individual product below to see specific directions for use.