Bought some monel wire to sieze some shackles. the shackles are galvanised and will be under water much of the time on piles. Is monel OK? Have heard it might react with the galvanised.
On our club moorings, I have seen the eye of the steel shackle corrode away completely in one season when it was moused with monel wire and immersed in seawater. We normally use black nylon ties rather than monel for mousing.
Galvanising on shackles and mooring chains rarely lasts two years in the Fal estuary. Some folks attach old anodes to the first metre or two of chain below the buoy to help preserve the galvanising a bit longer.