Attacking Pool Scale and Stains

Simple solutions for annoying problems

Keeping your pool in pristine condition requires a precise balancing of various elements. When not properly maintained, scale and stains can develop and become a problem, however, never fear – Doneman's Pool Centre has some handy hints on how to rid your pool of this pesky nuisance.

What is pool scale?

Scale appears as white, calcified deposits. It is created by excessive calcium & unbalanced water chemistry – typically either high PH, alkalinity, hardness, or a combination of any three. High PH and/or the total alkalinity cause an increase in the amount of carbonate ions. This combination creates calcium carbonate, which is more commonly known as scale.

Scale is obviously unattractive on pool walls and floor, but it can become a real problem if it builds up in the plumbing, restricting the water circulation and filtration, or if it builds up on equipment, causing equipment failure and the premature need to replace equipment. If scale occurs, you must test & adjust the water chemistry. Then a metal sequestering agent designed for calcium should be added to the water to remove scale. This binds to the metal and prevents it from depositing as scale and stains.

What is a stain?

Typically stains result from unwanted water contaminants such as metals (i.e. iron, copper and manganese), which find their way into pool water via water used to top up, salt added to the pool, liquid chlorine, algaecides containing metals, leaves from algae, oxidation and scale.

What causes stain and scale?

Metal stains most commonly appear shortly after the PH is raised or when you add chlorine. Fibreglass pools are particularly prone to metal stains. Organic stains can sometimes look similar to metal stains but are usually left by algae or leaves that sit in the pool for a while, leaving behind when cleaned up.

Metals can colour the water with a variety of colours, typically green, blue or yellow. When this happens the water will still be very clear and transparent. If the water is cloudy or murky it is very unlikely to have anything to do with metals in the water. If the colouring is from metals, lowering the PH slightly and adding a metal sequestering agent should remove the colour.

Doneman's Pool Centre has a range of products that can be used to prevent and remove stains and scale:

• Nail the Scale
• Multi Stain Remover
• Metal Solution

All are available in the swimming pool supplies shop so drop in, pick some up and feel free to ask our friendly team for their tips and tricks as you do.