First Time Buyers

There are five groups of chemicals commonly used with swimming pools and spas:

Sanitisers - these chemicals kill any micro-organisms present in the water (bacteria, viruses, algae). They are normally chlorine or bromine based chemicals.
Shock - chlorine or oxygen based chemicals used periodically to break-up impurities that accumulate in the pool water. Shock the pool every two weeks in the season or if you get a large build up of algae.
Water balancers - used to make your pool water comfortable to swim in and not corrosive to the pool fabric and equipment. They are pH adjusters, alkalinity builder and calcium builder.
Algaecides - these chemicals stop the build up of algae on the pool sides or in the water, which can turn your pool green
Clarifiers - These chemicals are used to keep pool water clear and treat a cloudy pool. There are two kinds, flocculants and coagulants. They work by causing microscopic pollutant particles in the pool to stick together, allowing easy removal by filtration.
Test Kits - It is very important that your pool water is tested regularly particularly for chlorine or bromine levels. This allows you to keep the right levels of chemicals, protecting both anyone using your pool and the pool itself. You will require a test kit.

Sanitisers

Sanitising agents come in a number of different kinds, which one is right for you depends mainly nature of your local water supply.

Maxi tabs and mini tabs are stabilised chlorine (trichloro isocyanuric acid) which will reduce the alkalinity and the pH. Use them in hard water areas. They can be placed in the skimmer or in a floating dispenser where they dissolve slowly.

Stabilised chlorine granules (sodium dichloro-isocyanurate) does not reduce pH and alkalinity so they are best used in soft water areas. Mix up with warm water in a plastic bucket and add to the pool.

Bromine tablets do not reduce pH or alkalinity. They do not smell of chlorine. They can be placed in the skimmer or in a floating dispenser where they dissolve slowly.

Please be careful with all these chemicals as they will bleach your clothes.

Shock

Shock treatments are used every two weeks during the pool season to break-up accumulated pollutants in the pool water. It is especially important in keeping outdoor pools free from algae.

Chlorine shock (calcium hypochlorite granules). Use on most large swimming pools. Mix with warm water in a plastic bucket and add to the pool every two weeks. Leave overnight before using the pool.

Oxygen shock (potassium peroxysulphate). It is quick acting and does not smell of chlorine. Used on jacuzzis and hot tubs. Dissolve in water in a plastic bucket and add directly to the pool water. Leave for 30 minutes before using the pool.

Please be careful with all these chemicals as they will bleach your clothes.

Pool Water Balancers

It is important to keep your pool water balanced, by controlling the acidity. Balanced pool water is essential for your sanitiser to work properly and keep the pool bug free and also to protect the pool fabric from damage. There are essentially two ideas involved in balancing pool water. Firstly the pool water must be brought to the correct acidity, or pH, usually between 7.2 and 7.4. This is done by adding pH plus if the pool water is too acid (pH less than 7.2) or pH minus if the pool water is too alkaline (pH more than 7.4). Secondly enough bicarbonate and calcium must be kept in the water to keep the pH stable, using Alkalinity Builder and Calcium Builder.

pH minus (sodium bisulphate). It is used to reduce the pH of pool water to between 7.2 and 7.4. It is required in hard water areas if chlorine granules or liquid chlorine are used. Mix with warm water in a plastic bucket and add directly to the pool.

pH plus (sodium carbonate). It is used to increase pH of pool water. It is required in pools using maxi or mini tablets (trichloro isocyanuric acid). Mix with warm water in a plastic bucket and add directly to the pool.

Alkalinity Builder (sodium bicarbonate). It stabilises the pH of the pool. It is required in soft water areas. Add directly to the pool and agitate with pool brush to dissolve.

Calcium builder (calcium chloride). It is used to increase the calcium level in soft water areas. A shortage of calcium will lead to pool grout marbelite and concrete being dissolved by pool water. Add directly to the pool and brush to dissolve.

Algaecides

Algae will build up in the pool especially if you do not maintain a good level of chlorine or bromine in the water. These build-ups can turn your pool water green and produce slimy films on pool services. Algaecides are added to the pool when it is filled and a smaller amount each week to prevent the build up of algae. If there is a severe build up of algae it will be necessary to shock the pool at the same time as adding algaecide.

Clarifiers

Used to treat cloudy water and keep your pool sparkling clear.

Flocculant - The flocculant used on large pools is Aluminium Sulphate. It forms a mat on the filter that allows it to filter finer particles. It is a solid that is added to the strainer after back washing the filter.

Coagulants - Sparkle is a coagulant normally used on small to medium sized domestic pools. It makes the particles of solid in the pool stick together so they are more easily filtered out.

What does my pool require?

Hard Water areas - Chlorine Tablets, pH minus, Shock, Algaecide, Sparkle, pH / Chlorine tester or test strips

Soft water area - Chlorine granules, pH plus, Alkalinity Builder, Shock, Algaecide, Sparkle, Balanced water tester or test strips.

Hot tubs - Hot Tub Starter Kit