It could be a nail bobby pin or a pop can.
What causes metal stains in pool.
Staining is caused by organic matter such as algae inorganic metals or water trapped beneath plaster surfaces.
If you suspect a stain is caused by iron try the vitamin c test.
Managing and preventing stains especially those from metal oxidation can be challenging.
Any metal item that can rust also can stain your pool.
Copper has more of a light green or even turquoise look to it when it gets oxidized.
High or low ph can lead to metals coming out of solution to stain your pool.
Simply dropping a metal item in the pool can cause rust stains.
If you have ever seen discolored water or pools with metal stains that s an obvious sign of metal content in your water.
In the vast majority of pools metal staining comes from iron.
Nothing bothers pool owners more than those unsightly blotches and discolor ations on an otherwise unblemished pool surface.
These typically produce only isolated rust stains where the metal object was laying on the surface and do not raise metal levels in the water.
Heavy doses of copper algaecide can lead to a blue green staining of pool liners.
Iron is fairly common in well water but rare in municipal water.
Iron copper manganese can come out of solution if your pool water has high levels of metals.
Many lawn and garden fertilizers can contain high levels of iron copper manganese and other heavy metals.
Iron is from well water corrosion of iron pipes and fittings and will result in rusty brown gray or greenish brown stains.
Place 15 to 20 vitamin c tablets in a sock and crush them.
Maintaining proper ph in your pool is important to mineral stain prevention.
Heavy rains and flooding with mud or mulch entering the pool will also elevate metal levels.
In addition to objects like bugs and leaves falling into your pool or algae turning the water green you can find metal stains along the walls of the pool.
The metals that commonly cause pool stains are iron manganese copper.
For example calcium stains appear as white crystals or patches around plaster grout.
These orange stains are from rust.
This will result in blue green teal black or dark purple stains.
The brown stain might be caused by the ioniser that deposits iron metal in your pool you need to clear the stains using ascorbic acid then consider reducing iron metal levels in your pool by draining and refilling a portion of your pool water or use a metal remover such as proteam metal magic to remove metals through the filter and avoid brown stains when you shock your pool or when ph is low.
While copper is a common cause of pool stains the accumulation of other minerals can lead to staining as well.
Iron when oxidized turns brownish or orange in color.