In maintaining the flow of seawater, with CF-8M cast stainless steel impeller ( its component equivalent of type 316 stainless steel ) and for type 316 stainless steel main shaft, you can without any problems. When the pump stopped working, crevice corrosion and pitting corrosion is likely to become a serious problem. But if using more lively and easy due to corrosion of cast iron to make a considerable pumping of wall thickness box, the cathodic protection of cast iron in downtime can play a role. When you pump, cast iron boxes under cathodic protection must make under the effect of polarization of stainless steel, but moving water dimension for cathodic protection. In addition, long-term working pump may alternate the use of both sea water into fresh water and when you play a protective effect.