All electrochlorination systems require the feed water to have a minimum salt content to generate sodium hypochlorite (biocide). A distinct advantage side-stream systems have against full flow or in-line treatment systems, is the ability to use an alternative electrolyser feed supply to generate the required biocide. Average seawater has a salinity of 35 practical salinity units (PSU). When treating ballast water with salinities below 25 PSU, an alternative feed source with a higher salt content must be used to operate the SeaCURE system. The Aft Peak Tank (or similar) can be used for storing feed sea water. This allows SeaCURE system to continue to treat even when the main ballast water flow is fresh or low salinity brackish
SeaCURE system uses a treatment process that requires the equivalent of approximately only 1% of the ballast water flow to feed the electrolyser. In this way, the storage tank capacity does not need to be excessive large whilst still maintaining full ballasting capabilities (to treat 50,000m³ of ballast water the tank capacity would be 500m³).