Abstract: A water treatment composition for treating a body of water is provided that provides visual feedback to the end-user of the effectiveness of the composition. The composition contains a majority of calcium hypochlorite particles; and an effective amount of colored particles containing an oxidizable pigment oxidizable dye and a water soluble material. The colored particles release the oxidizable dye to the body of the water to provide a transient color to the recreational water during dissolution of the composition in the body of water, the transient color providing a visual cue to the end-user signaling of the biocidal activity of the composition. Also provided is a method of applying the water treatment composition to recreational water.

Abstract: The invention relates to a method of treatment of bodies of water such as recreational pools, spas and hot tubs with maintenance doses of water treatment chemicals to achieve consistent sanitization and aesthetically pleasing levels of properties such as turbidity. The amount f the maintenance doses is based on the volume of water to be treated in order to achieve hygienic and clear water. The method can bt automated for accurate, consistent and safe treatment of water such as found in swimming pools, spas or hot tubs.

Abstract: The present invention relates to a method of inhibiting the growth of killing algae, bacteria, yeast and/or fungi in a recirculating water system which comprises adding to the water a polymeric biguanide and an adjuvant of the Formula (1) or a salt thereof: wherein: R1 is an optionally substituted C8 to C12 or C18 to C22 alkyl group; and R2 and R3 each independently is H or optionally substituted C1-4-alkyl.