Battle of the Solar Covers Solar blanket vs. liquid solar pool cover

We all want to save money and resources, but liquid solar pool covers are commonly overlooked. So, what is a liquid solar pool cover? To put it simply, a liquid solar pool cover (or blanket) is an evaporation suppressant. The liquid solar blanket is often compared to putting a lid on a boiling pot of water. It creates an invisible barrier on the surface of the water and helps to control the rate at which the vapour escapes from the pool.

What is a solar blanket?

Traditional Solar Blanket

A traditional solar blanket or solar cover is a large sheet of plastic, used to maintain water temperature by reducing heat evaporation. Covered in air-filled bubbles (much like bubble wrap), the solar blanket or solar cover sits on the surface of your pool creating a barrier and reducing water evaporation.

Plastic solar blankets differ in price, depending on the thickness, colour, and on the size of the pool to be covered. Generally, plastic solar blankets range from about $50 to $300.

Liquid Solar Pool Cover

Liquid solar covers are pretty much just like they sound! This specially formulated liquid is a combination of alcohol and calcium hydroxide, creating a microscopically-thin film on the surface of the pool. The liquid formula is so thin that you'd never be able to see it, or feel it while it's in the pool.

Liquid solar blankets are not meant to heat your pool or replace your heater, they simply retain the warmth from the sun therefore keeping the water warmer for longer and preventing heat evaporation. Less evaporation of course means having to add water to the pool less frequently, resulting in cost and energy savings.

Are Liquid Solar Pool Covers Safe?

When it comes to adding more chemicals in to your pool, we can understand the cause for concern. However, in this case, studies have shown that liquid pool covers are safe for swimming in and "found that when the liquid pool cover was used as recommended, toxic risks of exposure were negligible."

Most products are biodegradable and safe for the environment, your garden, and bathers when used correctly.

Why is pool evaporation important?

When evaporation occurs, only pure water leaves. This of course means the water left in the pool will have a higher TDS (total dissolved solids) reading and higher calcium hardness. This in turn affects the amount of balancing chemicals, chlorine, and filling water you need to continually put into your pool.

If the source water you're filling your pool with has metals or phosphates, that's another potential expense, since getting rid of metals and phosphates ends up costing money for labour and chemicals.

As warmer water evaporates from your pool, the total temperature drops as well. Reducing the amount of water that evaporates will naturally keep your water warmer.


When does evaporation occur most in your pool?

  • When your pool has a large surface area
  • When your water temperature is higher than the surrounding air
  • When it's windy
  • When it's humid
  • When there's strong radiation from the sun

What is better? Solar blanket or liquid pool cover?

Now you might be asking yourself why you would use a liquid solar cover rather than a physical solar blanket. While there are pros and cons for each, one of the biggest reasons simply comes down to the size and the storage required to keep a solar blanket in good condition!

Why use liquid solar cover instead of a plastic solar blanket

  • no need to cover and uncover the pool every day
  • easier to store
  • doesn't break down like plastic
  • no risk of drowning or becoming trapped under solar blanket
  • ease of use
  • reduce costs associated with heating your pool


Some pool owners are even convinced they use their pool less because they dread having to deal with their solar blanket every time they get in and out of their pool.

On the other hand, the liquid solar blanket continues to work when people are swimming in the pool. The tension formed at the surface of the water is broken by the swimmers but reforms quickly.

How to use liquid pool cover

  • Purchase the right amount of liquid pool cover for a swimming season. The "right amount" will depend on the size of your pool.
  • With circulation running, add liquid pool cover product to the skimmer (this disperses the monomolecular layer on the surface of the water). If you want, you can also pour the right amount of liquid pool cover directly into the pool. You may have to manually circulate the water so that the liquid cover properly covers the surface
  • Create a schedule to add more liquid pool cover, at least one time a month. Keep and sticking to a schedule will make sure that the liquid pool cover is effective.
  • If desired, use a physical solar blanket and liquid solar blanket at the same time for double the protection

Now you've got the low-down on solar covers, get some helpful tips for maintaining your pool!