Understanding Pool Surface Staining: Causes, Colors, and Prevention
Spotting discoloration on your pool plaster or tile can be alarming. Whether it is a dark patch in the deep end or a rusty stain near the steps, pool surface staining is a common issue for homeowners.
Knowing what caused the stain is the first step toward restoring your pool's clean appearance. Here is a look at the most common types of pool stains, what causes them, and how to prevent them.
Identifying Stains by Color
Different metals and organic materials leave distinct colors behind when they interact with pool water and surfaces:
- Brown, Tan, or Green-Brown: These organic stains usually result from decomposing leaves, twigs, berries, or acorns that sat too long on the pool floor.
- Red, Rust, or Orange: These metallic stains are typically caused by iron or copper oxidizing in the water, often stemming from corroded equipment, well water, or foreign debris like hairpins.
- Black or Dark Grey: Persistent dark spots can indicate black algae growth, which embeds deep roots into the plaster, or severe scale deposits mixed with heavy minerals.
The Root Causes of Staining
Pool stains generally fall into two categories: organic (from living matter) and metallic (from minerals or corroded hardware).
- Corroded Pool Equipment: When pool heaters, copper heat exchangers, or non-sacrificial ladder anchors begin to rust or wear down, metal particles leach directly into circulation.
- High Metal Content in Fill Water: Tap or well water in certain regions contains high levels of dissolved metals like iron, copper, and manganese that precipitate out when exposed to chlorine.
- Neglected Organic Debris: Leaving wet leaves or organic matter sitting on your pool floor for even a few days will leach tannins directly into porous plaster.
How to Prevent Future Stains
Preventing stains is much easier than removing them. Keep your pool surface spotless by following these proactive habits:
- Skim and Brush Weekly: Brush your pool walls and floor weekly to prevent fine particles, dust, and organic matter from settling and bonding with the plaster.
- Use a Metal Sequestrant: If your fill water is high in minerals, adding a monthly sequestering agent binds to metals and keeps them dissolved in the water rather than staining your surfaces.
- Balance Your Chemistry: Keep your pH and alkalinity balanced to prevent acidic water from eating away at metal components around your equipment pad.
By identifying stains early and maintaining consistent water chemistry, you can keep your pool surfaces looking pristine all season long contact us-
