How To Remove The Red, Green, or Purple From Your Pool


  3 out of 5 stars on 16 ratings
(Click on a star to add your rating)

There are times when your swimming pool will change colors after adding chlorine or shocking your pool. The colors may vary from green, red, brown, purple or black. The reason behind this color change usually indicates the presence of minerals (metals) in your swimming pool. The chlorine added to the swimming pool oxidizes the metals and will cause a chemical reaction that becomes visible in your swimming pool.

Click Here for Metal Sequestrant (Used for Iron, Manganese, Copper, and Calcium)

Step by Step


Step 1

While there are treatments that can be added to your pool to clear the problem, you may also want to find out what the source of the metals in your swimming pool. Metals in your pool water may come from several sources. If you water comes from a well, then you may want to check metal content in your well. City water may have traces of metals due to old rusty pipes that are going from your treatment center to your home. Other sources may be pumps, heaters, old copper piping and algaecides.

Step 2

Once you have determined the source, you can now test for the type of metals in the pool. If you don't have the proper test kit, you can purchase one or take a water sample in to be tested.

Step 3

In general, a greenish tint to the water usually indicates that your water may have either copper or iron. If it is a deep thick green and your water is starting to cloud up. There is probably an algae in your pool and you should follow these steps.


Click Here for Metal Sequestrant (Used for Iron, Manganese, Copper, and Calcium)

Step 4

A red or brown tint to the water will usually indicate traces of iron in the water. Sometimes, it can be caused by maganese or copper.

Click Here for Metal Sequestrant (Used for Iron, Manganese, Copper, and Calcium)

Step 5

A purple or black tint to the water points towards manganese. If you see black spots forming on the pool wall, you likely have black algae.

Click Here for Metal Sequestrant (Used for Iron, Manganese, Copper, and Calcium)

Step 6

Once you have determined the source and type of stain, you can use a metal remover. Before using a metal remover, you will want to make certain that you read the instructions on the label.

Click Here for Metal Sequestrant (Used for Iron, Manganese, Copper, and Calcium)

Step 7

After allowing the pump and filter to run for at least 12 to 24 hours, the discoloration should begin to clear. If the condition improves slightly, you may need an additional dose of the metal remover.

Step 8

Once the water condition has improved, you can turn the pump and filter off. Brush down the walls and keep the pump and filter off for at least 12-24 hours to allow everything to settle.

Click Here for Pool Wall Scrub Brushes

Step 9

After everything has settled, you can vacuum to waste to remove the debris from the swimming pool. Depending on the source of metals in your swimming pool, you may need to use a metal remover as a weekly maintenance to prevent any further discoloration of the water.

Step 10

If the metals stained your pool's surface, you can use a stain remover to get rid of the stains.

Click Here for Metal Stain Remover


(1 to 8 of 8)

InyoPools Product Specialist  Posted: 5/23/2017 

Ivan A - Give the procedures outlined in this guide a try to eliminate the metals in your pool system.

 Posted: 5/21/2017 

I have a pool problem for a week. It turns purple from Friday afternoon to Monday last week. Is a 10,000 gallons plaster pool that's is indoor. It is a bromine system.
Ph was above 10ppm and bromine was 4. By Monday it turns dark purple (I can provide you pictures) after draining the pool and place new water it was fine, lilac color start after we start recirculation and found out that Nitrates were above 200 initially and then after changing the water nitrates are 180ppm. Bromine is not picking up and Ph is 7.6 now


Anonymous  Posted: 6/23/2015 

If it is really purple algae the chlorine will get rid of it along with a wire brush. It is probably a purple stain caused by the copper algaecide added over the years to the pool to control algae. Then the alkalinity gets low and you go to raise the ta and the purple line on the pool forms almost instantly. if you can't get it off with a wire brush then it is probably a stain. Some stain treats may lighten it up but really won't take it completely off. the only thing you can do is drain and acid wash.Try the wire brush 1st, the stain treat 2nd and the acid wash 3rd. good luck and keep the ta over 80.



InyoPools Product Specialist  Posted: 5/30/2015 

Mon - It's certainly worth a try. Metals will have an impact on chemical stability, and this is a problem in many rural areas that have hard water. If you are looking for a better less costly solution to "feel pf water" you might consider converting to a Salt Chlorine Generation system.

 Posted: 5/27/2015 

After many hrs of searching for an answer to maganese in my rural water. I am currently using your methods. On my way out to brush sides down on pool. The pool above ground 24'x 54". After I waste water out I plan on using a metal trap when adding water back into pool. Will this keep from having reaction to chlorine products? I have used Soft Swim products for last 2 yrs. Way to costly and fought Algea all last summer. Love the feel of the water but HATE the cost and time consumed keeping pool clean!!!

Anonymous  Posted: 5/12/2014 

Went to several pool stores no one knew how to get rid of purple algae.

 Posted: 2/28/2014 

I have a pool business and I would like to know why today I clean jacuzzi filters when I pull out filters was all blue and vef
fore about 2 ,year ago filters came black got be metal in the water,my cuestion is what kain a meral is,I think is a cooper because rhis jacuzzi has some cooper pipes,so what I can doto fixed with out replace the cooper pipes?


 Posted: 11/20/2013 

Interesting images and information. I would add that when using a test strip, if you have sequestrant in the water, it won't give you an accurate metal test. You need to use a tester like EZ-DX Digital Water Test Reader which tests for TOTAL metals.

Also, the only way to get the metals out of the water is by using CuLator Metal Eliminator and Stain Preventer. It binds the metals onto a polymer inside a bag that goes into the skimmer basket. If you just use Metal Out or Metal Free, you aren't removing the metal from the water only sequestering the metals and the problem will return in a week or two.
Check out