Stains are one of the most irritating detriments to their investment that a pool owner can endure. To address this problem, the source of the stain must be identified, and the appropriate solution introduced as soon as possible.
How to identify and remove the two types of pool stains -
Metal or rust-based - Metals can accidentally be introduced into pools from well water or corrosion from copper pipes.
Organic - Leaves, berries, and other organic debris can also leave stains if allowed to settle on pool surfaces.
The best way to distinguish metal from organic stains is by colour. Different colour combinations provide good indicators of exactly what substance is causing a given stain. We have provided more insights below.
GREEN AND BROWN STAINS - These stains are most likely organic stains caused by leaves or other plant matter.
RED AND BLUE STAINS - These stains are more than likely from brightly coloured berries; check the area around the pool for the offending bush.
BLUE, GREEN AND BLACK STAINS - When a stain is a mixture of dark blue, green and black, and there is no evidence of organic matter, it is likely to have been caused by copper.
GREEN, BROWN AND RED STAINS - This combination indicates iron as the culprit.
BROWN, BLACK AND PURPLE STAINS - This dark colour combination is caused by manganese.
Once you’ve got a good idea of the cause of a stain, it’s time to test the theory and confirm the source of the problem. If an organic stain is suspected, try applying a small amount of chlorine directly to it. An organic stain will come away easily.
Metal stains, on the other hand, react best to ascorbic acid, the kind found in citrus juices. The best method is to apply crushed vitamin C tablets to the stain, and see if it is removed or lightens.