Corroded bath tap tops

[Steve Messy]

Around 5 years ago I competed a bathroom make over. I installed a water fall mono lock tap on the new bath and all was well for a couple of years when my wife noticed some corrosion to the tap tops. The tap was sold as chromed brass but I am guessing that is the body only as the tops are made of cheap inferior metal. Matching tap in the basin and no issues.
We have a water softener install and an electric shower that does run above the taps but even so, surely they should not corrode like this ?
Does anyone know where I might get replacement tops for this type of tap?
Thanks for any suggesting offered.

 

[blup]

They shouldnt corrode like that, that quickly, even with a dripping shower Manufacturers change tap design frequently so if you cant find an equivalent set, time for new ones.

 

[oldbuffer]

1. Looking at the corrosion pattern, I think the tap levers are chromed over "pot" metal.
2. Pot metal is often an alloy of zinc and aluminium.
3. I have "Vado Elements" taps at home. The bodies are chromed brass, but the handles are pot metal. They have corroded, fortunately where the internal splines are, so not visible.
4. We also have a water softener, and I suspect the traces of salt in the water have "de-zincified" the pot metal.
5. As blup above, time for new taps.