*
*
*
When black color staining shows up on a vinyl liner, among the an initial questions that pertained to mind is if algae or metals led to it.

You are watching: Black stains on vinyl pool liner

Copper, iron, and also manganese deserve to precipitate out of solution leading to pool liner stains, i beg your pardon generally show up black, brown, or grey. The metals might be introduced right into the pool via the fill water or indigenous improper pH causing corrosion of tube or heaters. The presence of steel staining have the right to be evidenced by treating a small part of the area v a vitamin C tablet. If the stain has been caused by metal, it will lift from the liner. Any remaining stains can be treated in a comparable manner using an ascorbic or citric mountain stain lifter. If this does no work, the stain is likely due to an organic source such as black color algae. After removing the stains, a metal sequestering product must be offered to prevent any further staining.

Black staining from algae

Black algae are tenacious organisms through a chlorine-resistant coating that require a variety of steps to remove. They show up as a collection of tiny black spots typically on the liner’s seams, close to the measures on the ladder railings, or about light rings. Black color algae execute not usually grow on the vinyl’s smoother surfaces (i.e. walls and floor).


To remove these stains, an initial scrub the black algae utilizing a nylon brush. To reduce the pH come a minimum 7.2 will increase the chlorine’s effectiveness. Then, super-chlorinate the swimming pool (normally to 10 parts per million totally free available chlorine) and add a dose of a quaternary (quat) type algaecide. The pH need to then be boosted to a more neutral selection (e.g. 7.4) to avoid the liner from wrinkling.

Mould on pool liners

If stains room still present after dealing with for metals and black algae, another kind of grey/black stain have the right to occur as result of the expansion of micro-organisms on the backside of the liner. These micro-organisms can produce dyes that room soluble in the plasticizers provided to make the vinyl liner pliable. The microbial dye wicks v the liner creating an unsightly, irregular-shaped blotch.

These stains can be decreased on the exterior side of the liner by supervisor chlorinating the water for a period, yet they will most likely reappear due to the fact that the stain is emerging on the backside of the liner.

See more: Is Quahog Rhode Island A Real Place, Quahog, Rhode Island

A polyethylene obstacle used in between the pool walls/floor help to stop this type of staining that is resulted in by these micro-organisms.