Coronado gets the same hard water as the rest of the county, and the minerals build up in every home. From the historic cottages to the towers, the signs are the same, scale on the fixtures, film on the glass, scale in the water heater, and the part you can't see, mineral buildup inside the plumbing itself. In homes kept up to island standards, that buildup is worth paying attention to.
Treatment splits into softening and filtration. Softening removes the minerals, and everything downstream benefits, the pipes, the appliances, the fixtures, the finish on the glass, and the way a shower rinses. Filtration handles the rest, taste, odor, and the larger question of what's in the water, which island households ask about as often as anyone. The systems do different jobs and often go together, and a vintage cottage and a high rise unit call for different setups.
The conversation runs plain and unpressured. What your water carries, what each option does, what fits the home, and what the maintenance involves over the years. Every recommendation comes with the reason behind it, and the decision stays yours, made at your pace. Years of buildup can look like a big job, and the setup is often simpler than people expect.