Q.....We are having our pool refurbished and are having much debate over styles. My wife wants to opt for tiling in a very dark colour or even black. Any thoughts?

A.....That immediately leaps to mind is that dark finishes show marks very easily. Where a small amount of calcium scale will be almost invisible on light colours it stands out on dark. This does not have to be from the pool water but from dribbles from the copings evaporating. There are also problems with dark grouting where acid washing can lighten the colour and a non-uniformity of colour results. Additionally, where dark grout is used great care has to be taken to prevent it staining either copings or other grout. Where dark stone is used be careful not to seal it with the wrong sealant which can lead to the sealant releasing and showing as a white bloom on the surface.You may also want to consider whether the dark tiles will effect visibility in your pool, particularly where safety is concerned.

Q....As my son suffers with eczema, my local pool shop has suggested we add a salt-chlorinator to our family pool. Can you explain how this will help?

A....I would take your pool shop’s advice. Salty water is softer, and kinder to the skin and is altogether much nicer to swim in. A salt chlorinator is a great way to automate the addition of chlorine in a home pool. A salt chlorinator will produce chlorine on-site from a salt solution using a process called electrolysis.

Q.....Our pool seems to be developing brownish stains around the edge of the water surface – what should we do?

A....Invariably this is being caused because your pool water is not correctly balanced. It could be causing corrosion of metallic parts in or near to the pool. Test your water to check the pH level of the pool is between 7.2 and 7.8 while also checking alkalinity levels. Pop down to your local pool shop for more advice and to ask about acid-washing to remove the stains.

Q.......We have a large outdoor pool with a marbelite finish in need of repair. We have had two quotations, one for applying a new quartz material and one to re-render with marbelite - which material would you choose?

A.......If the existing backing renders and screeds are sound, strong and waterproof, says Alan Pugh, either quartz or new marbelite can be applied.
Quartz would offer you more colour choices, is more resistant to staining and with underwater light can give an attractive 'sparkly' surface finish. Marbelite is considered more waterproof and, unlike quartz, can be applied in spring or autumn with weather protection. I suggest that you ask your contractors whether they provide an air dome (with a water-filled skirt) to protect the work and ask them for references for their sub-contractors of their experience and record of working on hotel, club or local authority pools. It is then for you to choose which material you prefer - on colour and cost - and your confidence in which contractor would provide the best workman ship.

Q.......I've been thinking about installing a drowning detection device after seeing the recent news story about a child being rescued from a pool in Bangor. Will this system work reliably in any pool?

A.......Shape, size and depth of pool often require a customised system, and the supplier will be able to advise you after surveying your pool. Remember that underwater surveillance equipment works most effectively in clear water. If you can not see through the width or length of your pool with your goggles on, you will need to make some improvements to your water treatment regime.
By implementing good operating practices and using continuous PAC dosing, pool water can be improved to an excellent quality. As the water gets clearer, you could find that you use less chlorine and pH correction chemicals, more than off-setting the cost of using PAC.
Of course if you do not invest in a surveillance system, water clarity is even more important, especially when you take into account glare turbulence on the water surface.
Good quality water is not just great for bather comfort - it helps saves lives too.

Q.......Why can't I get breakpoint? I understand the theory but my combined chlorine are always the same or more than my free chlorine.

A.......It could be numerous reasons, but let's try and start afresh. The solution to pollution is dilution. You should throw away 30 litres (6 gals) every time somebody uses your pool and bring in 30 litres of fresh water. Generally a TDS meter reading will tell you if you are adding enough. Look at your bathing load and always ensure that you have a good reserve of free chlorine to deal with your predicted bathing load. Try and get your bathers to use toilets and showers to cleanse themselves and not your pool for this purpose. Make sure that you are adding a flocculent control pH as close to 7.3 as possible make sure your staff are trained.

Q.......My daughter has seen a marked deteriation in her asthma since taking up a part time job as a lifeguard. The doctor has suggested there is a link. Is she right or is it just a coincidence?

A.......I am not a doctor, however there has been some research carried out recently in Germany which does suggest a link between pool hall atmosphere, chlorine and asthma. The results have not been regarded significant by those who know, at least in this country. It would also appear that the connection is also linked with bad housekeeping where the atmosphere is contaminated with 'combined chlorine', which should be kept down to a very small amount is a well regulated pool facility.

Q.......I have been told to backwash weekly even though my gauges say that my filters do not need it. What should I do?

A.......The reason for this is that filter sand can 'cake' due to greases, nasal mucous, gels, etc. that pass through them. This would reduce the filtration area, extending your turnover time but also exposes these 'caked' areas to colonisation by pseudomona and other bacteria. So, it is advocated by all the lead bodies, that we backwash weekly with enough velocity to fluidise and expand the sand bed, breaking up these areas and disinfecting all the filter media. Also remember to backwash prior to a period when the pool will not be used e.g. last thing at night to ensure that the filter bed can re-compact to its filtering efficiency.

Q.......Every spring the water in my pool has turned green. I know I have to close down at the end of every season, but am I doing it correctly?

A.......The general recommendation is that you shock dose the pool with an accredited brand of chlorine granules to the value of 5 to 8 ppm (parts per million). Also add an algaecide to the manufacturers' recommendations but remember, do not do this too soon in case the weather warms up again. Once added, winterise your pool in the usual way and fit a winter debris cover.