What is the partial range is it between 0.45 to 0.85mm

Hi Crystal, We are the manufacturer of Clorox Pool&Spa products. Filter Sand Plus is not 20 grade silica sand, which has a typical particle size of 0.45 to 0.85 mm. Filter Sand Plus replaces 20 grade silica sand with a natural zeolite mineral which has a unique three dimensional honeycomb structure which provides a larger filtration surface area. Filter Sand Plus can filter out contaminants that are 10 times smaller than what can be filtered using 20 grade silica sand. Using only half of the amount that would be used with sand, Filter Sand Plus provides excellent filtration, increased time between backwashes, and clean, clear water. When replacing filter media, we do recommend that the sand filter manufacturer's instructions be followed as both our product and 20-grade silica sand can be dusty in nature. If the dusty material is allowed to enter the pool, either due to not rinsing or an issue within the filter itself, the dusty material can contribute to cloudiness and other potential chemical reactions with compounds in the water. If you have any other questions or pool care concerns that you would like to discuss with us, please give us a call at 1-800-SOS-POOL (767-7665). Thank you.