Tag Archives: solar pool cover

What causes a pool solar cover to break up?

We are often asked why has my swimming pool’s bubble cover started to degrade? The usual pattern is that you find little bits of white plastic floating in your pool water. You wonder where they have come from and eventually find that they are from the underside of your pool cover. The bottom of the bubble has degraded and fallen off.
A typical failure looks something like the image below.

Picture of a failed swimming pool cover

Typical break up of a pool cover

The material becomes brittle and the cover literally falls apart. This type of failure happens when either the cover has reached the end of its useful lifespan or something has happened to shorten its lifetime.

The plastic that the cover is made from contains antioxidants and chemicals to protect it from breakdown by UV light from the sun. These chemicals don’t last forever and as the cover ages so these chemicals get used up. Either the oxidisers in the pool water will break the plastic down or the UV light from the sun will. Or a combination of both.

This process should happen after about 6 years but sometimes it happens after only a few years. Why is this? In almost every case it is because of chemical attack on the plastic from the pool water. Excess chlorine in the pool water, whether for a prolonged period or intermittent periods, will attack the stabilisers and and deplete them in advance of their usual lifespan. Once the UV stabiliser is depleted by the chlorine the sunlight will finish off the job of breaking down the plastic.

What can I do to prevent this happening?

Many pool owners say that they do have too much chlorine in the pool and this may be so for most of the time but if you shock dose the pool and put the cover on straight away you will harm the cover. Sometimes you get high levels of chlorine under the cover but don’t realise you have done it.

Pool covers come with solar protection sheets to cover them when they are off the pool. These should always be used.

Roll the cover off the pool so that the bubbles are down. That way the sun can’t shine on them.

Are some covers better than others?

Yes. The higher the grade of material used the longer the life span of the cover. Three grades are available 400, 500 and 600 micron. This refers to the thickness of the material, the thicker the better.

The new Geobubble Swimming Pool Covers will last much longer not only because they are made from 500 and 600 grade but the additives are better and the shape of the bubble is such that it does not have weak corners that are always the first to fail.
So to summarise.

  • Don’t let the cover come in to contact with high chlorine levels when shocking
  • Make sure you don’t accidentally over chlorinate and if you do take the cover off
  • Roll it up with the bubbles down
  • Put the solar protection sheet on

What is the best swimming pool cover?

How do you choose a good swimming pool cover? Here is some infomation to help you choose.

Developed from the same technology as bubble wrap, pool covers are made from two layers of plastic one flat layer on top bonded to a bottom layer with air bubbles in it. The air bubbles mean that the cover will float on the water. Pool covers are often refered to as bubble covers. The first pool covers were coloured blue because it seemed a sensible colour to choose.

Research on pool covers soon discovered that not only did they keep the heat in the pool by stopping evaporation but by a “greenhouse” effect they could also heat the surface of the water. This lead to the covers being refered to as Solar Covers. It was then discovered that if you made the bottom, bubble, layer of the cover in silver plastic then the silver reflected the heat back in to the pool like silver foil on a roast joint. This lead to them also being called heat retention covers. Because of the blue top and the silver underside they are mostly known as blue/silver covers.

Another consideration is the thickness of the plastic that the layers are made from. The thickness of the plastic is measured in microns. One micron is 1,000th of a milimetre. Some cheap covers are 100 or 200 microns thick but the standard thickness for our covers is 400 microns or 0.4mm. So our standard cover is made from 400 micron material with a blue top layer and sliver bottom layer and is refered to as a “400 micron blue/sliver”.

The next level up in quality is a cover made from 500 micron thick plastic. 500 micron covers come with a blue top layer and a gold bottom layer. Hence they are refered to as a “500 micron blue/gold“. The thicker material means these covers are harder wearing and they are heavier too. They do not retain much more heat than the 400 micron blue/silver but they do have a longer warranty. If you have a big pool the extra weight, 25% more, of this cover may be an important consideration for you.

All bubble covers for swimming pools have chemicals in them to protect against ultra violet light. The 400 micron blue/silver has a 3 year pro rata warranty and the 500 micron blue/gold’s is 4 year.