A method of making a solid water treatment product, wherein said solid water treatment product has an optimal dissolution rate, comprising the steps of: 1) providing the ingredients to make a solid water treatment product, wherein said ingredients are selected from the group comprising: a) Active Ingredients; b) Optional Inactive Ingredients; and c) Fluorescent Tracer, wherein said Fluorescent Tracer is selected from the group consisting of inert fluorescent tracers and active fluorescent tracers; wherein said solid water treatment product consists essentially of from about 10% to about 99.99% of said Active Ingredients, from about 0 % to about 98% of said Optional Inactive Ingredients and from about 0.01% to about 10 % of said Fluorescent Tracer; 2) preparing the solid water treatment product; 3) placing the solid water treatment product in test water; 4) providing a fluorometer; 5) using said fluorometer to measure the fluorescent signal of said fluorescent tracer in said test water; 6) repeating the measurement of fluorescent signal from Step 5) at regular intervals; 7) determining the rate of dissolution of solid water treatment product by analyzing the increase in fluorescent signal measured in Step 5) with time; wherein if said rate of dissolution of solid water treatment product is optimal, then Steps 8) and 9) are optional, if said rate of dissolution of solid water treatment product is not optimal, then Steps 8) and 9) are required; 8) optionally adjusting the preparation of said solid water treatment product, based on the rate of dissolution determined in Step 7), in order to prepare a solid water treatment product with an optimal dissolution rate; 9) optionally repeating Steps 3), 4), 5), 6), 7) and 8) as necessary in order to obtain a solid water treatment product with an optimal dissolution rate. 1) providing the ingredients to make a solid water treatment product, wherein said ingredients are selected from the group comprising: a) Active Ingredients; b) Optional Inactive Ingredients; and c) Fluorescent Tracer, wherein said Fluorescent Tracer is selected from the group consisting of inert fluorescent tracers and active fluorescent tracers; wherein said solid water treatment product consists essentially of from about 10% to about 99.99% of said Active Ingredients, from about 0 % to about 98% of said Optional Inactive Ingredients and from about 0.01% to about 10 % of said Fluorescent Tracer; a) Active Ingredients; b) Optional Inactive Ingredients; and c) Fluorescent Tracer, wherein said Fluorescent Tracer is selected from the group consisting of inert fluorescent tracers and active fluorescent tracers; 2) preparing the solid water treatment product; 3) placing the solid water treatment product in test water; 4) providing a fluorometer; 5) using said fluorometer to measure the fluorescent signal of said fluorescent tracer in said test water; 6) repeating the measurement of fluorescent signal from Step 5) at regular intervals; 7) determining the rate of dissolution of solid water treatment product by analyzing the increase in fluorescent signal measured in Step 5) with time; wherein if said rate of dissolution of solid water treatment product is optimal, then Steps 8) and 9) are optional, if said rate of dissolution of solid water treatment product is not optimal, then Steps 8) and 9) are required; 8) optionally adjusting the preparation of said solid water treatment product, based on the rate of dissolution determined in Step 7), in order to prepare a solid water treatment product with an optimal dissolution rate; 9) optionally repeating Steps 3), 4), 5), 6), 7) and 8) as necessary in order to obtain a solid water treatment product with an optimal dissolution rate.