The invention relates to a method suitable for optimizing a biological treatment of pools, wherein the method comprises the monitoring of one or more system parameters, wherein said one or more parameters are a carbonate hardness (KH), a global hardness (GH), and a potential of Hydrogen (pH), wherein the pH is maintained within a range of about 6.5 to 8.5, preferably within a range of about 7 to 8, and most preferably within a range of about 7.2 to 7.6, characterized in that a ratio of the KH and GH (KH/GH) is maintained within a range, wherein said range is preferably about 60 % to 95 %, more preferably about 65 % to 90 %, and most preferably about 70 % to 85 %. The invention further relates to a system suitable for optimizing a biological treatment of pools.