As pool owners will all know, stains can become a massive annoyance. They seem to appear at the worst of times and seem to be noticed by everyone other than you, for example, a guest at a pool party you might be hosting. Well, you may be relieved to know, there are many solutions to stains in your pool and many preventative measures. We will hope to run you through all of those on this page, as well as giving some advice toward pool maintenance.

This page will offer you a few steps you can follow that will help prevent and stop pool stains from occurring in your swimming pool. A swimming pool should not be a burden, but rather, a way to exercise and relax. With those pesky stains gone, you will be able to do just that.

So, if you want to know how to prevent stains from occurring in your swimming pool, read here, for we will tell you everything you need to know. Let’s get into it, shall we?

Identifying and Removing Pool Stains

Unfortunately, pool stains cannot be removed with a wet cloth and a good wipe down. Nor can, in most cases, eliminate the stain by draining out the pool. We will go over cleaning pebblecrete pool stains, and tell you how to identify the stain. Identification is the first step in removal; here are a few ways to identify individual pool stains:

  • Organic stains will often be brown, and can be caused by animals, leaves, and plants;
  • Green Algae will turn the water of your pool green and speckle on the surface of the pool;
  • Mustard Algae, named for its color, grows in shady areas of your pool, for example, areas that are covered by branches of trees, and has a wispy texture;
  • Black Algae is most typically confused with other types of stains, and will form speckles and clusters that grow roots in your pool; black algae will often grow inside your drains and vents, meaning you cannot get rid of it by draining your swimming pool;
  • Iron will form stains that range from hues of yellow to dark brown;
  • Copper can tint the water in your pool an unnatural blue before it begins to stain the surface but can be grey, brown, and black. It can also be purple.
  • Manganese, which can be found in well water, causes your pool to tint purple or black.

Your swimming pool should be a relaxing place. It should not be a spot that gives you anxiety or can make you unwell. By dealing with these stains, you are ensuring you get to make your pool a viable place to relax in.

Removal and Prevention of Stains

With identification out of the way, we can now move onto the removal and prevention of stains. Additionally, if you notice odd smells without staining, you may want to contact a professional to assess the cause of the odor. In this way, this problem will be tackled early on and resolved as soon as possible.


Mottling is sometimes confused with staining, but mottling cannot be gotten rid of. Mottling occurs quite normally and is subject to variations in hue and shading of your plaster. Mottled can usually not be removed unless you paint over it.

Rust Stains

Rust, which can be caused by metal objects falling into your swimming pool or caused by a crack in your pool which is allowing water to get to your pool’s rebar steel. It may also be that the rebar steel is too close to the surface. Additionally, in vinyl pools, galvanized steel walls can break down through exposure to damp soil. This can be prevented by repairing the crack, replacing the rebar steel, or painting over and adding wall foam.

Metal Stains

Metal stains, which are quite common, create reddish-brown stains and can be very irritating for swimming pool owners, for they are usually the most obvious and hard to remove. You can test these stains to determine which metal is causing them. Oftentimes, metallic stains can be prevented and controlled with chemical treatment.

Mineral Deposits

Mineral deposits are very common, and we have likely seen them before around our taps, our showers, or our baths. They occur when scale film is mixed with dirt and oil. Mineral stains can be removed easily, and you can use a chemical treatment on them.

Organic Stains

Organic stains are usually unavoidable when you own an outdoor swimming pool. They can occur from leaves leaching tannins into your pool; acorns falling into your pool, or even worms and algae. These can all leave stains in your pool. Thankfully, the treatment is straightforward. You should never use household chemicals to clean these, however, as you can introduce phosphates into your pool water. Acid treatment will often work.

Waterline Stains

Grime on the surface of your swimming pool can combine and create waterline stains or scum lines as they are more commonly known. You can lower the water level and clean them with enzyme cleaners.

With the help of this page, you now know how you can treat dirty stains in your swimming pool, and how to prevent them. Swimming pools are a lot of fun and a great way to relax. With this page, you needn’t have anxiety over annoying stains ever again!