Test before you treat
The first move with any well, new or inherited, is a water test, because what comes out of the ground varies from place to place and you cannot sensibly pick treatment for water you have not measured. A test tells you the hardness, the iron, whether there is bacteria, and whether salt has crept in. Spending on a softener or a filter before you know the numbers is guessing, and it is how people end up with equipment that does not fix their actual problem.
What is common out here, and what fixes it
Hard water, the kind that leaves scale and spots and eats water heaters, is very common and a softener handles it. Iron that stains fixtures rust-orange is also common and has its own filter. These are ordinary, solvable South Texas well problems. The right treatment is whatever the test points to, not a one-size package, and a good well pro reads your results and matches the equipment to them.
The coastal concerns
Closer to the water, two things deserve attention: salt, because coastal aquifers can carry brackish water that no softener really fixes and that sometimes means going deeper for a better source, and bacteria, because a well is an open path into the ground and should be tested for it, especially after flooding. If a test comes back with salt or bacteria, that is a real answer, not a scare tactic, and it changes the plan.
- Test first; you cannot fix what you have not measured
- Hard water and iron are common and fixable
- Near the coast, watch for salt and bacteria
Texas requires drillers and pump installers to carry state licensing under separate occupational codes covering each trade. Local groundwater district rules can add their own requirements for spacing, well logs, completion, and shutting a well down properly.