Spa Shock or Oxy Fresh. Chlorine free oxidiser - Oxidises contaminants from your pool or spa without the use of chlorine. Should be used weekly in your pool or spa to eliminate algae growth and to kill bacteria.
Active constituent: Potassium Monopersulphate
Regular treatment should be 30gm per 2000 litres of spa water every week or double the dosage if the spa has heavy use.
Suitable for use with all ionisers. Cheaper to buy in bulk.