The enhanced Baquacil CDX System will provide you even greater assurance of crystal clear water throughout the season. Research and development has shown that maintaining crystal clear pool water using Baquacil is to maintain a Baquacil Oxidizer residual. The Baquacil CDX System does just that. This system was developed for Baquacil pool users who have water mold challenges and/or have a hard time maintaining a Baquacil Oxidizer residual. Like the standard Baquacil System, it's hassle-free, chlorine-free and easy to use.With the new Baquacil CDX System, no regular use of algaecide is called for, but in areas where algae problems are prevalent we recommend the use of either the Baquacil Algicide or Baquacil Performance Algicide.Note: All plaster pools must be treated with Baquacil Metal Control at a rate of 1 bottle per 10,000 gallons of water, regardless of metal analysis results.