No comment on the shower head construction. Probably Pot Metal, maybe Zamak.
Back in the dark ages when I was stationed in Florida, anywhere near the St Johns river stunk to high heaven. I was at Mayport, near the Naval Station and spent most of my off time near Palatka. What we had there was sulpher water. Military installations and many older homes had an aerator to decrease the sulpher content. But in truth, once you got past the smell, it probably was the healthiest water to drink. Swimming in the backwaters of the St Johns like Welaka Springs kept mosquitos away. They might light, but never bit.
Older buildings used galvanized iron piping. Newer structures used PVC plastic. Copper was a "no go", it wouldn't stand up. It seems nothing was proof against the sulpher in the long term. The only real protection against it is to invest several thousand $$ in a water treatment facility. That needs to be rebuilt on a regular basis. I have seen solid plastic kitchen faucets and shower heads that seemed to stand up better. But even they didn't last long. A few years at best.
Best suggestion I can make is to learn to live with it. And put a few shower heads on the shelf so they're handy when you need 'em. Anything that has a "spray" function. Garden hoses, kitchen faucets, shower heads, the like. The family I associated with in that area had been there for generations. Many generations.
Sea Story Alert. My friend's grandfather grew up on an island near the current "Cross Florida Barge Canal". The Oklawaha river. His mother was a busy woman in those days. She would put him in a pit, along with a chicken for company. If the chicken got to squaking and raising hell making a fuss, she knew an alligator was near. Far better than a dog for that application. When I knew the man (in early 70s), he was in his 80s. And still the best guide in Putnam County.
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