Natural Chemistry's Pool Magic Spring and Fall PhosFree gives pool owners with a treatment designed to make opening and closing their pool much simpler and easier, along with adding PhosFree to eliminate any phosphates in your water. Utilizing natural enzymes that stabilize pool water through the winter, it eliminates much of the prep work commonly involved during pool opening, and virtually eliminates the formation of water rings, stains, while protecting pool liners and finishes. This treatment also makes acid washing unnecessary, saving you time and money.