Removing a pool surface stain can be very time consuming and frustrating even for a season pool cleaner. Weather your pool is a plaster pool or a fiber glass the process is similar. There is two ways I have found to get out the stains. You can use a stain removing agent to pull the stain out of the surface of the pool. Once the stain is gone you will need to bring the chemicals, especially the chlorine back very slowly.
The down side of using a stain removing agent is when you bring back the chlorine levels unfortunately the stain returns with it. This can be very frustrating and costly not to mention the closer time of the pool every time this is attempted.
The other way I have recently learned about is to remove all chemicals from the water and raise the acid level to twice the lowest level of 7.0. Now this can only be attempted in a fiberglass pool or plaster. Never in a vinyl liner pool or you run the risk of damaging your liner. Once you have removed all chems and lowered the ph you will need to run the pool for two days till all the staining is gone and the walls and floor are uniformed color.
You will want to add some metal out to the pool and then give it a good brushing to remove any residual coating from the walls and floor of the pool. Then start to bring the PH back up with sodium bi-carb till you reach a 7.4 on your test kit. Then start to bring up your chlorine very slowly with your chlorinator or salt system. Do Not Put Tabs In Skimmer! doing that will raise your chlorine far to quickly and your stain will have a good chance of returning over night.
Once your chemicals have reached the proper balance check them daily because they have the tendency to drop over the next week or so. Follow these steps and you will have a fighting chance against your stubborn pool stain.
Good Luck.
P.S. Make sure if you go with a stain removal agent, that it will not raise your phosphate levels. That is a whole new ballgame you don’t want.
Comments? Remove I guess