Greenish brown stains commonly appear on swimming pools because of algae growth and fallen leaves. These kinds of stains are easy to deal with since you can simply apply chlorine directly on the discoloration and keep scrubbing until it comes off.

But how about the odd purplish-black stains on the walls of your pool? How do you remove those? It can be difficult to clean these kinds of pool stains, especially if you don’t know what caused them in the first place.

So today, Clark County Pool & Lawn will share this guide on how to remove the two main kinds of pool stains — organic- and metal-based — and how to identify their cause based on their color.

Organic Pool Stains

Organic-based pool stains are caused by organic matter, such as leaves, algae, dead bugs and critters, dirt, and oils, that has settled on your pool’s surfaces. The color of the stain tells you what organic material caused the discoloration. Here are some of the common colors that organic pool stains take on.

  • Greenish brown: most likely caused by leaves, algae, mud, or other types of plant matter
  • Reddish blue: most likely caused by brightly colored berries fallen from nearby trees and bushes

If you think the pool stain is organic in nature, confirm your theory by performing an organic stain test. You can do this by applying a small amount of chlorine directly to the stain. If it’s organic, it should come off or at least fade because of the chlorine.

Once you’ve confirmed what kind of stain you’re dealing with, you can continue scrubbing it off with chlorine. If the stain is affecting a large portion of your pool, you need to super chlorinate or “shock” the water. This means adding three pounds of calcium hypochlorite for every 10,000 gallons of water.

Metal-Based Pool Stains

Metals can be accidentally introduced to your pool due to corroded water pipes, rusted pool parts and components, or metal items that have fallen into the water. These kinds of stains are more difficult to remove since they don’t react to chlorine, so you’ll likely need to call a pool cleaning service.

Another issue with metal-based pool stains is that they can take on the same color as organic stains, which is why you need to perform the organic stain test. Below are the common colors of metal-based stains and their likely sources:

  • Blue, green, black: This combination indicates the presence of copper in the water, which is commonly caused by corroded water pipes.
  • Red, green, brown: This combination indicates the presence of iron in the water, which is common for pools that are filled using well water.
  • Brown, black, purple: This dark color combination indicates the presence of manganese, which is present in well water and municipal water supplies.

To confirm if a stain is caused by metals, apply a bit of ascorbic acid powder on it. If the discoloration lightens, then that means it’s a metal-based stain.

After that, it’s time to call a professional pool service. They’ll need to determine the metal content level in your pool water and the source of the stain first before coming up with a removal solution to make sure that the discoloration doesn’t happen again. This is why it’s not advisable to remove metal-caused stains yourself.

Make sure to hire a pool repair professional with ample experience in dealing with different kinds of stains so they can help you prevent the problem from reoccurring.

Swimming Pool Maintenance Services in Las Vegas

Clark County Pool & Lawn offers a range of residential pool cleaning and maintenance services in Las Vegas, including water balancing, leak inspection, and stain removal. We’ll help you keep your pool chemically balanced and clean all year so you and your family can make the most of it without worrying about maintenance-related issues.

Fill out our online form to request a free estimate on stain removal services.