If you don’t know what causes rust spots in pool, it can be difficult to remove rust stains from your pool surface. When you see rust, that’s often an indication that there’s some metal involved, and it can occur in a tiled, fiberglass or plaster pool. Start by knowing what could be causing it and how you can keep it from happening or what can make it go away. Below are some reasons rust spots may be occuring in your pool.
Oxidation of Water
The water you use in your pool may have metal in it. If your pool has many tiny rusty spots, the chances are you’re filling your pool with water that contains metallic fragments. Filtering the water or adding a “metal out” additive is your best bet in this case. You may also need to vacuum and sweep your pool more often as well. Alternatively, scrub the spots with a brush or acid wash the spots directly. Another option is to use magnets to collect tiny bits of metal.
Concrete Rust and Rebar
Rebar refers to intersecting metal shafts typically found under the plaster of your pool. Rebar will rust through the plaster if it’s placed within an inch or less of the pool surface. The corrosion is usually worse underneath, so if left untreated; rusting rebar can cause serious problems.
Trace amounts of iron in your pool can also lead to rusting, which should be treated before it spreads throughout the pool and costs much more to repair. A possible remedy is to cut out the rusted section and patch it will gray masonry cement.
Metal Items in the Pool
Dropping a metal item in the pool can lead to rust stains. Whether it’s a bobby pin or nail, metal items that can rust can also stain your pool. Be sure to remove such items as soon as you discover them. The more acidic your poolis, the faster the problem escalates, but if you end up with a stain, get rid of it using rust removing liquid or a steel brush you can purchase at your local pool supply store.
Soluble and Colloidal Iron
Soluble iron or “clear water” rusts when it comes into contact with the air. This leads to the formation of reddish-brown particles in the water. You can avoid this problem by feeding chemicals into the water to oxidize the iron, which you can then filter out using a mechanical filter. Another option is to add chemicals into the water to coat the iron, so it will not receive oxygen.
Colloidal iron is rust that’s in the water, but it doesn’t rust because it’s bound with other substances. Dealing with this may involve adding polymers that will cause the iron to form large clumps that you can easily filter away or add chlorine to facilitate the oxidation of iron from other substances.
Understanding what causes rust spots in pools makes it easier for you to make an informed decision on the best possible remedy. It can be due to metal items being in your pool, or your pool water being too metallic. Make sure to remove the source of metal quickly, and treat the water if necessary.