For the more discerning pool owner who wishes to test for additional parameters. Deep Blue Pro 6-Way Test Strips provide a quick and easy way to test your swimming pool water. They offer tests for free chlorine, total bromine, pH, total alkalinity, calcium hardness & cyanuric acetic. Simply dip the strip in the water and remove immediately. Hold horizontally for 10 seconds (do not shake excess water from the strip), then compare pads against the colour chart on the test strip bottle.Stock note: In an effort to provide the quickest possible delivery for our customers we may ship an alternative premium branded product if stocks are low.? These brands will only be Blue Horizons, Deep Blue Pro, Relax or Swim Fresh, all established for a long time in the water treatment industry.