Black Spot oh Argh

Swimming pools can be a problem, sometimes things occur with them and you just don’t have the answer. I’ve worked with pools, both in their construction and maintenance for nearly twenty years and, without wishing to blow my own trumpet, I am rarely stuck for a solution no matter what the problem is. I in fact regularly receive telephone calls from other gîte owners or their agents to discuss various pool problems and I am seldom stumped for an answer. All that changed though when my friend Tate phoned me up and said that he had black spots on the bottom of his pool, which were getting worse by the day, and refused to be brushed off.

As I wasn't sure what he meant I took a ride over to his place and lo and behold there they were, and true to his account no amount of scrubbing would remove them. Being at a loss to explain the problem let alone suggest a cure, I took my leave of Tate and headed back to where I knew I would find the answer. I thought it was algae, but I had no idea what algae, and what should be done about it escaped me. I decided to take the advice that one of my English neighbours had once given me. Besides running several gîtes in different areas of France, he also sells young willow plants for ornamental hedge building in his spare time. I can say that, from my horticultural days, I do know a bit about willows and knowing my neighbour Pete I knew that he almost certainly didn’t, so I asked him what he did when customers asked him for information about things concerning willows. His simple answer was I Google-it, this is a bit of information that has stuck with me and so I got straight on to the computer and Googled "black mould on swimming pools.

There were as expected hundreds of websites offering information and cures, but what I discovered was somewhat surprising. Firstly Black Spot Algae is not algae, it’s a bacteria, and secondly, and not so surprising, it is tremendously difficult to get rid of. Before I go any further I must point out that Tate’s pool is tiled and in general Black Spot Algae is only a problem for tiled pools as the bacteria cannot get a grip on liners and fibreglass. After searching many sites and even more pages it became clear that this was certainly a problem that was going to be difficult to solve. Invariably the websites said that the only way to remove the bacteria was a lot of hand scrubbing, as the bacteria gets its roots into the grouting between the tiles and then forms a hard crust on the top which is resistant to chemicals and all but the most vigorous scrubbing. I don’t know about you but on a pool that is 2 meters deep I cant envisage doing this without sub-aqua equipment and a strong back, neither of which I process.

My initial solution was to test out one of my theories, which at least stood some chance of working, as it would have been the method that I would have employed had the pool been empty. It was to use a pressure washer. Easy enough in the shallow end, but the deep end presents an altogether different scenario. Undaunted I attached the pressure gun, with duct tape, to the end of the telescopic pole that is used to brush the pool, taped the trigger in the “on” position and used the on-off button on the machine to control the operation. It worked a treat with the one exception, which was that it quickly covered the top of the water in the pool with the hard black caps of the bacteria making it difficult to see what I was doing. This meant that I had to stop once or twice to allow the skimmers to clear the caps away; it wasn’t that bad really, it was a hot sunny day, and lying by the pool in the sun chatting to Tate was, as always, a pleasure. Having finished and then cleaned the pool the filtration system needed to be thoroughly back washed and then the pool shocked with high doses of chlorine and anti bactericide.

I must emphasise that this is a quick and temporary fix, during the winter the pool will either need to be emptied to cleaned more thoroughly, which as it is a saltwater pool I’m reluctant to suggest, or it will need a stronger chemical treatment. I do have an idea what chemical to use, but if it doesn’t work I will have wasted another year and I’ll have to go through the same cleaning process during the summer. This bacterium truly is one of the most persistent and if you get it all I can say is good luck, but watch this space.

souris in my pool

A Problem at the Pool, I need Agatha Christy

You know what they say " a friend in need is a pain in the bum" well that’s not always the case, my friend Tate has a small handicap which means his mobility is a little impaired and a few years ago he (actually it was his mother the late and much lamented June who I "nicknamed drippy" as she was always asking me to fix her leaks) who asked if I would construct a pool for him. I explained that I was no professional and only helped friends build their own pools. Well Tate was in no shape to pick up a shovel or push a wheelbarrow so with a little help from my friends we duly build a 10m x 5m pool with a special entrance which Tate and I designed specifically for him. It had a nice Seahorse emblem at the bottom. and was a concrete construction with a tiled finish. It turned out very well and a very grateful Tate now uses it every day that weather permits.



This year Tate called me to discuss a problem with the pool. I wasn’t doing much so I said I’d visit and see the problem first hand. On arriving he explained that he had a problem with Souris (mice). The problem was that they kept getting into the pool, whether they were using it for leisure or just to have their equivalent of a pint who can say, unfortunately once in the pool they couldn’t get out and they would swim around and around until they died. The skimmers would then suck the mice up and they would go into the filter nets. Tate couldn’t get down to the skimmers to remove them so they would accumulate until the pool cleaners or a mate turned up, whichever was the sooner. Now on a good day Tate’s a reasonably nice chap, considering he’s from the Devon, and he didn’t like the thought of all these rodents dieing so he was seeking a serious answer to a serious problem.

After a short deliberation I explained that as I saw it there was a choice of three simple solutions. The choices were: 1. Get some cats and hope they remove the problem at source (it would take an awful lot of cats and who would look after them in the winter). 2. Build a mouse proof barrier around the pool (not very practical) 3. Put a ramp in so that the mice could escape the watery death once they’d had their drink and freshened up.
Yer" he said in his Devonshire accent, “Ow bis I gwaina doun?" which roughly translated means How am I going to do that? I explained that it would be easy; all that was required was to attach a polystyrene float to a short piece of wood and attach the other end to the pool entry ladder. "Is’n gwain a wurk?" (Will it work?) I was confident that it would. The next time he had some friends over they built the aforementioned Souris ramp and believe it or not it works a treat. Since the beginning of May not one mouse has met with a watery end, there have however been 2 frogs who have not managed to fathom out how to use the ladder, but then we all know how dumb frogs can be.