Metals can change the water colors when chlorine is added, usually yellow, green (clear), or brown, and this can be complicated by the reflection of the water against the color of your pool surface (i.e. blue pool with yellow tint from metals = emerald green water). When iron is left untreated, it can settle and leave stains on the pool surfaces.
If you are not able to have fresh (non-well) water delivered, and are stuck with well water, then the more “pre-filtering” of iron you can do to physically remove it before treating chemically the better. Some folks have had decent success placing layers of dishrags, paper towels, or pillow batting in the skimmer to catch iron/rust particles. Others place socks, micro-filters, or other products over the garden hose as they fill from the water source to serve as a pre-filter.
Your best and most reliable method of metals management is to add sequestrant to the water and replenish it periodically. Sequestrant is a chemical that binds to the iron in the water so that it can't form stains or turn brown. Sequestrant breaks down slowly, so you need to add more regularly. ProTeam's Metal Magic and Jack's Magic the Pink Stuff (regular), the Blue Stuff (fresh plaster), and the Purple Stuff (SWG) are some of the top sequestrants. You can also find other brands with similar products, some of which are noticeably less expensive. Sequestrants based on HEDP, phosphonic acid, or phosphonic acid derivatives are the most effective.