Potassium monopersulfate, more commonly called non-chlorine shock, is a substance that can rapidly oxidize swimming pool contaminates without the use of chlorine. Potassium monopersulfate is also called MPS, or Potassium peroxymonosulfate. MPS does not contain chlorine, as it is a potassium salt of peroxymonosulfuric acid.
Potassium peroxymonosulfate is marketed as a popular non-chlorine based shock. Its primary swimming pool use is to oxidize any contaminates in the water, leaving chlorine or bromine sanitizers already present in the water to focus on sanitizing the water.
Active Component (KHSO5.KHSO4.K2SO4), %
Bulk Density, g/L
Particle Size Distribution(0.850~0.075mm),%
Stability ,active oxygen loss/month, %
One of its greatest advantages is that bathers can reenter the water a short time after it has been added — typically about 30 minutes.
Also, it dissolves quickly, and does not fade liners. It works well with chlorine, arguably allowing chlorine to work more efficiently as a sanitizer. Using KMPS is highly recommended for indoor pools, where there is no sunlight or wind to help break down and carry away combined chlorine. For indoor pools, shocking with KMPS is recommended about once a week.