[crusty old prospector]

What about catholic protection?

[GingisK]

That helps with the electro-chemical corrosion; but, that isn’t all there is to sea water.

[GingisK]

I thought is wise to go some reading. It seems that filtered sea water does OK in plumbing systems when sacrificial electrodes are in use. But, the plumbing needs to to brass, copper, or bronze. No mention of plastic in the text.