We have a training pool that is just the right size for the small groups of students that Tony prefers to teach. It’s an ideal size to heat up, and in order to make it as comfortable as possible to spend extended periods of time on skills, we’ve taken a couple of measures to make the water as warm as we can. The first, which we fitted when we installed the pool, is a thermal cover that both warms the water and reduces algae growth. It looks like grey bubble wrap, and works like a bomb – it raises the water temperature up to four degrees higher than the air temperature (and if you don’t run the pump to mix the heated layers, you can get an impressive thermocline!). Of course, to get the benefit of the pool cover, it has to be on at least some of the time, which is a challenge during the summer months, when there’s always someone in the pool!
The second measure we took to warm the pool was to install solar heating panels on the roof. These panels consist of a fine network of tubes made of tough HDPE, through which the pool water is circulated and then returned to the pool. The existing pool pump is used (this is why we fitted a more powerful one than the size of the pool warranted when we did the initial installation) and the heat of the sun warms the panels directly, as well as warming the roof which warms the panels from below. We fitted them on the north-facing sloping area of our roof. As a rule of thumb the number of panels needed is one for every two square metres of pool surface. Our pool is 5×3=15 metres square, so we have 7 panels (which is 15 divided by two, and rounded down).
The pump has a manifold fitted, which allows us to decide when we pump water onto the roof, and when we don’t bother. During the winter, when it’s quiet, or raining, we can isolate the panels and just run the pool pump as normal. This also saves electricity during the time of the year when it’s most in demand inside the house.
The entire system was installed by our fellow diver Justin Gootman of Project Pumps, and we can highly recommend his and his team’s handiwork and professionalism. (At the same time and with great expertise they drilled us a well point, but that’s another story.)
I learned to dive in Cape Town in the month of July, and the training pool was 9 degrees and I was almost physically ill when I submerged myself. It was very unpleasant. For several years afterwards it was the coldest water I’d ever been in, until a freezing dive at Tafelberg Reef in the Atlantic took over pole position. I am happy to say that we at Learn to Dive Today are doing our bit to ensure that fewer Cape Town dive students have to suffer as I did!
