Hi, a standard transfer pump is not designed to transfer salt water. We are aware of people that do use standard transfer pumps to move salt water, but if they are not flushed thoroughly with freshwater after use (which often they are not), then the seals will be damaged and corrosion is likely to occur. This damage would not be covered under warranty.
You would need to look at a Chemical Pump which are built with stainless steel heads, fasteners and shafts, along with viton seals. These pumps are specifically designed for pumping waste water, chemicals, sea water, fertiliser and other caustic liquids.