These are minute organisms, invisible to the naked eye that can live in soil, in salt water or fresh water or in living things. All bacteria rely on organic matter for food and are therefore of significance to other life on earth. Many are harmless to man and live on dead organic material; others are beneficial, living in the digestive tract and helping with food breakdown; others are parasitic or pathogenic, causing disease.
Bacteria may enter a pool from the supply water, from the atmosphere, dust and leaves, but most commonly from bathers. In a single swim a person will shed something like 3 million bacteria and 0.5 grams of organic dirt.
When bacteria are present in a pool, they may multiply quickly, and if they are a harmful kind can cause disease in bathers. They enter the body either through the ears or nose or when water is swallowed.
This includes perspiration, body oils, urine, suntan lotion, hairsprays, skin flakes, mucus; also leaves, grass clippings, dust. Much of this provides nutrients for bacterial survival.
These are microscopic forms of plant life that get into pools through rain or wind. There are many types, some of which are resistant to routine chemical treatment. That is why shock treatment is necessary.
Algae do not cause disease, but they look unpleasant, colouring the pool a murky green, brown, red or black, depending on the type of algae present.
Although algae are relatively easy to control by routine sanitising and shock treatment, they can recur rapidly if they are not completely eliminated by the treatment.
They survive behind light fittings or around ladders and other fixtures where circulation may be poor so that the pool chemical has not reached them. They also exist in sump lines and solar heat lines. Thorough cleaning around such fittings and ensuring full circulation of the sanitiser is an essential part of algae control.
(One pool had a continuing problem with algae until it was discovered that the stepladder was hollow, providing a stagnant reservoir in which algae flourished, protected from contact with the pool sanitiser).
How chlorine works
Free available chlorine is needed to destroy bacteria entering pool water.
A generous dose is needed for this because, when chlorine is added to a pool, its first priority is to combine with organic material, algae, and bacteria already in the pool. It follows a set pattern of activity:
- When a chlorine sanitiser is added to a pool containing organic pollutants such as skin flakes, body oil, urine, or mucus, dust, grass clippings, bacteria, algae and so on, the chlorine first of all combines with these nitrogenous substances. It combines to form chloramines, compounds which can smell strongly of chlorine and irritate the eyes and nose.
- If more chlorine is available, its next priority will be to destroy the chloramines.
- And when all chloramines have been destroyed, any additional chlorine, known as free available chlorine, can destroy bacteria and viruses brought into the pool by swimmers.
If a pool is constantly in use during the day, pollution is constantly being introduced by bathers, so there may be no chance to form free available chlorine. Night time treatment may be advisable to overcome this problem.
Chloramines smell strongly of chlorine. If there is insufficient chlorine available to destroy chloramines, bathers will complain of sore eyes and a strong smell of “too much chlorine”.
In fact, there is too little. More should be added, to destroy the chloramines and provide free available chlorine.
The sterilisation action of chlorine is also influenced by:
- pH: As the pH rises, the rate of killing bacteria decreases. If the pH is too low, the amount of chloramines present increases. pH should be kept between 7.2 and 7.8.
- Temperature: The oxidising effect increases with temperature. At 27oC the rate is between two and seven times greater that at 4oC, depending on concentration and pH.
- Concentration: The time taken to destroy bacteria varies directly with the concentration of free chlorine – that is, if the concentration is doubled, the time required to sterilise will be halved.
Cyanuric acid stabilisers
When using Bluewater Granular Pool Chlorine (calcium hypochlorite) or Bluewater Liquid Pool Chlorine (sodium hypochlorite), free chlorine is rapidly destroyed by sunlight. Dose rate and frequency of dosing must take this into consideration.
This rapid loss can be overcome by using cyanuric acid (Bluewater Pool Stabiliser) as a stabiliser either alone or combined with chlorine. (NOT MIXED TOGETHER) added separately. It acts as an ultra-violet filter, so shielding chlorine from the destructive effect of the sun’s rays. To be fully effective, a minimum level of 30 p.p.m. cyanuric acid is needed. Too high a level can slow down the rate at which bacteria are killed, though, so care must be taken to see that the level does not become excessive.
Usually, with rain, splashing and refill there is sufficient dilution, but should the level exceed 100 p.p.m. the pool should be partially drained and refilled with fresh unstabilised water.
Bluewater Stabilised Pool Chlorine, EconoChlor and Stabilised Chlorine Tablets are chlorinated cyanurates.
Because it takes time for a sufficient level of cyanuric acid to build up, even when using Bluewater Stabilised Chlorine, Bluewater Pool Stabiliser should be used at the start of each season to provide the required minimum level of 30 p.p.m. cyanuric acid.
Superchlorination, shock dosing
Superchlorination refers to a specific, very high dose (up to 5 times the normal daily dose) of chlorine. It is given to enable oxidation (“burning up”) of high levels of organic matter including bacteria and algae, whilst still providing free available chlorine.
Superchlorination with Bluewater Granular Pool Chlorine or Bluewater Liquid Pool Chlorine is recommended at the start of each swimming season or for a newly filled pool. It may sometimes be needed after long periods of hot weather and prolonged pool use.
Shock dosing refers to giving twice the normal daily dose. It is recommended at regular intervals to “burn out” chloramines and algae not responsive to routine dosing. Shock dosing also prevents algae from becoming resistant to the daily dose rate.
Bluewater Granular Pool Chlorine
A granular formulation containing > 650 grams per kilogram of calcium hypochlorite. It is available in packs of 2 kg, 4 kg, 10 kg, 20 kg and 40 kg. Bluewater Granular Pool Chlorine is a low residue formulation. It is recommended that a premix be made (by adding the granules to a bucket of warm water). After mixing to dissolve the granules, allow the insoluble residue to fall to the bottom of the bucket and pour the supernatant liquid (the clear liquid above the residue) around the edges of the pool. Dispose of the undissolved calcium residue (this should not go into the pool as it will cause cloudiness & build up an artificial hardness). Bluewater Granular Pool Chlorine has three uses:
- To superchlorinate new pools, or at the start of each swimming season for pools using any Bluewater sanitiser. As a routine sanitiser for daily application. As a shock treatment for pools sanitised with all Bluewater chlorine products.
- Bluewater Granular Pool Chlorine is used to provide superchlorination and shock treatment in pools routinely sanitised with Bluewater stabilised chlorine products.
There are several reasons :
- The level of cyanuric acid stabiliser in a pool must be kept between 30 and 70 p.p.m. A level higher than 70 p.p.m. begins to slow down the speed at which bacteria are killed. It is therefore inadvisable to add the stabilised product at the rates required for superchlorination and shock treatment, as it would build up too high a level of cyanuric acid.
- The dose levels for both superchlorination and shock treatment are too high for comfortable swimming. Bluewater Granular Pool Chlorine, in common with all brands of calcium hypochlorite, rapidly loses chlorine to the atmosphere in the presence of sunlight & temperature. Therefore, after it has done its sanitising job, the level drops quickly back to a comfortable 1 p.p.m. High doses of stabilised chlorine would take longer to drop to this level.
Bluewater Liquid Pool Chlorine
Bluewater Liquid Pool Chlorine is a convenient “ready to use” chlorine that doesn’t require any premixing, nor leaves any calcium residue. It is available in 20 litre packs and contains 130 grams per litre of available chlorine.
The shelf life of this liquid product is less than for granular chlorine. As a guide, it may release approximately 1% of chlorine per month at about 20oC but this degradation will accelerate in the presence of sunlight or metals.
In general, use five times as much liquid chlorine as you do granular chlorine, for the equivalent chlorine level.
The level of free chlorine in the table below should be maintained for several hours prior to and during swimming activity by adding chlorine at the rate calculated from the chart. Always check the free chlorine daily, cyanuric acid levels monthly with a reliable test kit using fresh testing reagents and vary the dosage if necessary.
- SHOCK DOSING: During the swimming season shock dose once per week. After shock dosing the pH balance of your pool should be checked.
- WINTER MAINTENANCE: A shock dose once a month is necessary to maintain your pool in good condition during winter.
pH CONTROL: Liquid Pool Chlorine will increase pH. The pH should be tested regularly using fresh testing reagents. If it falls below the required level add pH Buffer (Preferable) or pH Increase. If it rises above, add pH Decrease.
Bluewater Liquid Pool Chlorine – Dosage Rates
|POOL VOLUME LITRES||STABILISED POOLS DAILY CHLORINE DOSAGE||UNSTABILISED POOLS DAILY CHLORINE DOSAGE|
|SHOCK DOSING||Four times the Daily Dosage||Twice the Daily Dosage|
|INITIAL START UP SUPER CHLORINATION||Seven times the Daily Dosage||Five times the Daily Dosage|
DO NOT EXCEED A CONCENTRATION OF100mg/l OF CYANURIC ACID
Bluewater Stabilised Pool Chlorine, or EconoChlor
Bluewater Stabilised Pool Chlorine is a granular formulation containing 600 grams per kilogram sodium dichloroisocyanurate. It is available in packs of 1kg, 2kg, 4kg, 10kg and 45kg. The 10kg pack is sold under the brand name EconoChlor.
This product is more stable than Bluewater Granular Pool Chlorine and is not so susceptible to degradation by sunlight. It is therefore a more effective & under-utilised sanitiser.
It is used for routine sanitising of pools. For initial superchlorination and shock treatment, Bluewater Granular Pool Chlorine or Bluewater Liquid Pool Chlorine is recommended.
Stabilisation of chlorine depends on a level of 30 to 70 p.p.m. of cyanuric acid in the pool water. Instead of waiting for this to build up by applying large daily doses of Bluewater Stabilised Pool Chlorine, it is recommended that the level be brought up to 30 p.p.m. by an initial does of Bluewater Pool Stabiliser.
If this is not done, the cyanuric acid level in the pool will be insufficient at first to stabilise the chlorine. A much higher dose rate would be needed for some days to maintain adequate chlorine levels until the cyanuric acid level has reached protective proportions.
The three main advantages of using Bluewater Stabilised Pool Chlorine are :
- It is added directly to the pool. No premixing is required.
- Because effective chlorine is retained longer in the pool, a far lower dose is needed.
- It remains in the water longer, killing bacteria and algae as they infect the pool.
Bluewater Stabilised Pool Chlorine Tablets
Bluewater Stabilised Pool Chlorine Tablets contain 900 grams trichloroisocyanuric acid per kilogram. They are available in packs of 1kg, 4kg and 45kg. Each tablets weighs 200grams. They are used for routine sanitisation of swimming pools. For initial superchlorination and shock treatment, Bluewater Granular Pool Chlorine should be used. The three main advantages of Bluewater Stabilised Pool Chlorine Tablets are :
- They provide a continuous supply of chlorine
- Weekly treatment is usually sufficient
- No premixing required
Bluewater Pool Stabiliser
Bluewater Pool Stabiliser contains 98% isocyanuric acid in powder form. It is available in packs of 1.5 kg and 45kg.
It is used to:
- Stabilise pools sanitised with non-stabilised Bluewater Granular Pool Chlorine
- Give an initial stabilising level of cyanuric acid when Bluewater Stabilised Chlorine products are used
Bluewater Stabilised Chlorine sanitisers contain cyanuric acid, a substance that protects chlorine from the destructive effect of ultra violet light. The level of cyanuric acid in a pool should be between 30 and 70 p.p.m. to achieve this protection. As it would take some time for such a level to build up using only stabilised pool chlorine, pools should be given a dose of Bluewater Pool Stabiliser at the start of each season.
Bluewater Pool Stabiliser Routine
Each spring, or when the pool is new, superchlorinate the water with Bluewater Granular Pool Chlorine.
Adjust water balance.
Add Bluewater Pool Stabiliser direct to the pool at the rate of 250 grams per 10,000 litres. This will result in a stabiliser level of about 30 p.p.m. Allow 12 hours for it to dissolve before adding the preferred Bluewater sanitiser.
Salt Water Chlorinated Pools
Super chlorinate the Pool by adding either of the following:
Bluewater Liquid Pool Chlorine – 2 litres per 10,000 litres of pool water
Bluewater Granular Pool Chlorine – 400g per 10,000 litres of pool water
If using Bluewater Granular Pool Chlorine, it is essential to dissolve the chlorine in a bucket of warm water. Premix by adding Bluewater Granular Pool Chlorine to the bucket of warm water – not the reverse. Stir well and allow the calcium residue to settle in the bucket before adding the clear solution to the pool.
Apply the solution to the surface of the pool around the edge. Circulate through the filter.
Winterising with Bluewater Chlorine Sanitisers
Bacteria and algae can grow in pools over the winter, so it is essential to maintain a level of chlorine to prevent more growth. Orica Chemnet recommends that pools be covered during winter to prevent build up of leaves, dust and dirt. Precautions should also be taken to prevent frost damage to the pool and its accessories.
- Vacuum and brush the pool thoroughly.
- Backwash the filter.
- Check that the water is balanced and adjust if necessary.
- Check the stabiliser level and adjust if necessary to bring it between 30 and 70 p.p.m.
- Check that the chlorine level is between 1 and 1.5 p.p.m. and adjust if necessary.
- Addition of ‘Bluewater Pool Algicide and Winteriser’ will help extend the properties of the sanitiser. With the filter running, add Pool Algicide and Winteriser direct to the water round the edges of the pool at the rate of 80 ml per 10,000 litres. Run the filter for at least 1 hour per 4,000 litres.
- During the winter check the chlorine level once a week and adjust as necessary.
- Run the filter for at least 1 hour per 4,000 litres once a week during the winter.
- Backwash before shutdown.
- Add 80 ml Pool Algicide and Winteriser per 10,000 litres every six weeks.
Always keep the container closed when not in use.
Take sensible precautions when using them – avoid splashing and do not eat or smoke while using the chemicals. Always read the label before use and follow the instructions. Note the first aid treatment listed for each product.
Chlorine products are corrosive and can damage the skin and eyes. They can also irritate the nose and throat if inhaled. (Do not allow tablets to come into direct contact with any other form of Chlorine based product or oxidising agent)
Follow the directions for disposal on the product label.
They should be stored away from the reach of children, in a cool dry place away from foodstuffs, other chemicals and combustible matter.
Baquacil is a non-chlorine sanitiser. It is used in conjunction with Baqua Shock and Baquacil Concentrated Algicide as part of a three-part system. Baquacil comes in 3litre packs and Baqua Shock comes in 5 litre packs. Baquacil Concentrated Algicide comes in a 1 litre bottle. All are liquid formulations.
BLUEWATER POOL FLOC
Bluewater Pool Floc is a preparation of aluminium sulphate for the removal of clay, turbidity or fine particles from pool water. It may be used with Baquacil and Bluewater pool sanitisers. It is available in packs of 1.5 and 25kg.
If a pool becomes murky or cloudy and the filtration system does not clean it, the water can be returned to a crystal-clear state by flocculation.
Bluewater Pool Floc provides a cloud of aluminium sulphate that settles to the bottom, carrying with it minute particles that would normally pass through the filter.
BLUEWATER SUPER FLOC (previously BAQUA FLOC)
Super Floc is for use in clearing hazy or cloudy pool water. It is specifically designed for use in treated pools it performs equally well in pools using both Chlorine & Baquacil systems. It is available in 1 litre and 20 litre packs.
Super Floc has the following advantages over other clarifiers:
- No need to adjust pH
- A liquid, does not require dissolving or dilution.
- Very efficient floccing properties.
BLUEWATER ALGAE SHOCK (previously Baquacide 798)
Algae Shock can be used as an algicide supplement in both Baquacil and Bluewater Chlorine pools. It is available in 1litre packs.
This product should only be used when either shock treatment with Baqua Shock or Bluewater Granular Pool Chlorine have failed to eliminate a stubborn strain, or to treat a very severe algal growth.
BLUEWATER FILTER CLEAN (previously Baqua Clean)
Filter Clean is an acid based cleaner for synthetic cartridge, diatomaceous earth, and sand filters. It is available in a 1litre pack.
Regardless of whether chlorine or Baquacil is used, all filters need to be properly maintained to remove unwanted particles of suspended dirt and debris. Each filter type requires slightly different maintenance procedures. The pressure gauge lets you know when the filter is working properly, when a problem exists, and when maintenance (backwashing or cleaning) is needed. The filter’s pressure gauge should be checked on a weekly bases and pressure noted.
Important: For chlorine treated pools, allow the chlorine level to drop to below 0.0ppm, a nil reading, before using this product.