---
title: "What Is Metal stain? Pool Glossary | Marina Pool Services"
description: "Metal stains are brown, green, or purple marks caused by iron, copper, or other metals in the water."
url: https://marinapool.multisites.ai/glossary/metal-stain
publisher: Marina Pool Services
phone: +1-817-896-1120
quote: https://marinapool.multisites.ai/contact
---

Water chemistry

# Metal stain

Metal stains are brown, green, or purple marks caused by iron, copper, or other metals in the water.

Metal stains show up as rust-colored spots, blue-green marks, or a dark tint in the water after you add chlorine. They come from metals in fill water, from corroding equipment, or from copper-based products.

Low [pH](https://marinapool.multisites.ai/glossary/ph) can pull copper from heat exchangers and cause stains. A test strip with a metals check helps find the cause. Fix the source first. Then a stain remover or sequestrant can lift the marks. Do not shock a pool with high metals until you test, because chlorine can lock the stain into plaster.

[Marina can helpPool Maintenance Services](https://marinapool.multisites.ai/our-services/pool-maintenance-services)

## Related terms

-   [Scale](https://marinapool.multisites.ai/glossary/scale)
-   [Copper ionizer](https://marinapool.multisites.ai/glossary/copper-ionizer)
-   [pH](https://marinapool.multisites.ai/glossary/ph)
-   [Fill water](https://marinapool.multisites.ai/glossary/fill-water)

## Need a hand with your pool?

Call or text and tell us what your pool needs. Estimates are free for qualifying services, and same-day estimates are possible when the schedule allows.

[Call (817) 896-1120](tel:+1-817-896-1120)[Get a quote](https://marinapool.multisites.ai/contact)

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