What Are The 5 Best Liquid Pool Covers?



Swimming pool ownership requires a large financial commitment, and saving money wherever you can will make a big difference over the long term.

Heating a pool is one area that can become a financial burden, causing your monthly bills to spiral out of control.

For this reason, the pool industry has created some affordable ways to keep your pool warm, with liquid solar covers being one of them.

With cost in mind, even the very best liquid pool cover is a borderline steal compared to traditional heating methods. 

Our Picks For Best Liquid Pool Covers

We found the best liquid solar pool cover (or solar liquid blankets) on the market, and ranked them accordingly:

Best Overall (Recommended)

Sunheater Shield, 32 oz. Bottle – Liquid Solar Blanket, Non-Toxic and...
Sunheater Shield, 32 oz. Bottle – Liquid Solar Blanket, Non-Toxic and...

    Best Liquid Twin Pack

    2 Pack SeaKlear Solar Shield 32oz 90245
    2 Pack SeaKlear Solar Shield 32oz 90245
    Natural Chemistry 07100 Spa Swimming Pool COVERfree Barrier Layer - 32oz...
    Natural Chemistry 07100 Spa Swimming Pool COVERfree Barrier Layer - 32oz...

    Best Liquid Solar Pills

    Aquapill Solar Pill Liquid Solar Blanket 12,000 gallons Pools(Various Pack...
    Aquapill Solar Pill Liquid Solar Blanket 12,000 gallons Pools(Various Pack...
      Auqapill AquaPill AP72 30,000 Gallon Solar Pill for Swimming Pool Heating,...
      Auqapill AquaPill AP72 30,000 Gallon Solar Pill for Swimming Pool Heating,...

        What Is A Solar Liquid Pool Cover?

        Liquid pool cover is a high-fat alcohol additive for your pool. It creates a molecular barrier on the surface of the water, trapping heat so it can’t escape.

        In pools, heat escapes from the surface of the water. This predominantly happens overnight. When the outside air temperature drops, it draws out the heat from the pool water.

        To cut down on this, you can cover the surface of the pool. 

        In the past, this was traditionally done using a bubble wrap-like bubble wrap-like solar blanket. But with today’s inventive technology, you can achieve almost the same amount of heat retention by using a liquid solar blanket

        Of note, unlike a traditional solar cover, a liquid cover won’t draw in heat from the sun. Rather, it’s only a barrier that prevents heat loss and water evaporation.

        However, all pools receive some form of heat from the sun and outside air temperature, and this is what the liquid cover is locking in. Over time, a rise in temperature can become quite substantial.

        Due to its molecular chemistry, the alcoholic liquid floats to the surface of the pool, providing it with an invisible blanket. When people dive in, the blanket disperses in the water. Only when the pool becomes still again, will it naturally reassemble. 

        For this reason, it’s recommended to not run your pump and filter system at night when using liquid solar cover. This is because the constant movement of the water will disrupt the cover during the hours when heat loss is most prevalent.

        Liquid pool cover is effective, but what it won’t do is actually heat the water. To do this, you need to use a heating method that will physically inject the pool with heat. 

        However, using a liquid cover with a traditional heating method such as a gas heater or heat pump will still save you money on your heating bills. You can heat the pool the “old fashioned way”, and then use the liquid solar cover to maintain it.

        2 Pack SeaKlear Solar Shield 32oz 90245
        2 Pack SeaKlear Solar Shield 32oz 90245

        Are Liquid Solar Covers Worth It?

        Whether or not they’re worth using is entirely circumstantial, as they might be a perfect heating method for one person, but totally inadequate for someone else.

        However, for their price, they should definitely be considered:


        • Cheapest heating method available
        • A single bottle can last up to 2 months
        • Easy to add to the pool
        • Safe to use and swim in
        • Biodegradable and environmentally friendly
        • Retains heat well
        • Prevents evaporation of pool water
        • Saves from topping up pool chemicals   
        • No wrestling with large solar blanket
        • Won’t clog filter or circulation system
        • Can use with traditional heating methods to maintain temperature


        • Does not heat the pool (will only keep heat from escaping the water)
        • Takes days or even weeks to see an increase in water temperature
        • Dependent on sunny days for a slow temperature increase
        • Large-size pools will require more liquid solar cover
        • Needs to be added to the pool weekly
        • Needs to be added more frequently in relation to pool use
        • Not as effective as a solar blanket
        • Won’t be as effective in pools where high winds are present
        • Rainfall will disrupt its effectiveness

        Answers To Common Questions

        Here are some common questions people are curious about when considering liquid solar cover.

        How Long Does It Last?

        This is dependent on the size of your swimming pool and how frequently you use it. Always consult the manufacturer’s dosage instructions, as it will vary from pool to pool.

        On average, you should get around 2 months of use from a single bottle of liquid cover. This is based on a 32 oz. bottle, and using 4 oz. per week with a 20,000 gallon pool.

        How Much Heat Can It Provide?

        Liquid solar cover doesn’t actually provide any heat to the pool water. It keeps heat from escaping the pool, especially overnight, which is when most heat loss occurs. 

        Of course, all pools are heated to a certain extent by the sun as well as the outside air temperature, and this is what liquid solar cover is working to keep present in the water.

        It will take a few days (maybe even a few weeks) but you will see a noticeable 5 – 10° rise in water temperature as long as the days are consistently hot and sunny.

        Does It Prevent Water Evaporation?

        That it does!

        On average, pools lose anywhere from ¼” to ½” of water every single day, which is equivalent to between 2 and 4 inches per week. As outside temperatures drop overnight, the warmth in the water turns into mist, escaping through the pool’s surface.

        With a liquid solar cover, it acts as a barrier so that water evaporation is slowed down. Obviously this is a good thing for you as pools require an additional 25,000 to 50,000 gallons of water annually to make up for evaporation loss. That’s a hefty water bill you can do without.

        Is It Safe To Swim In?

        Yep, liquid solar cover is perfectly safe to swim in, and it’s actually biodegradable. Once it’s dispersed in the water it becomes heavily diluted, so you won’t have any problems even if you ingest pool water.

        However, like all chemicals for pools, if you chug liquid solar cover straight from the bottle, you’re gonna have a bad time.

        Can It Clog Up The Pool Filter?

        With all the expensive equipment in your pool’s circulation system, this is a common concern. But liquid solar cover is perfectly safe for your pool equipment and won’t clog your filter

        In fact, due to its consistency, the majority of the cover will remain on the surface of your pool even while the circulation system is running. The cover molecules are so small that the amount that does go through the circulation system will pass right through the filter.

        Does It Work In All Weather Conditions?

        Liquid solar cover can be used in all types of weather, but it’s designed to be effective only in the most ideal conditions. 

        During storms, heavy rainfall will penetrate through the invisible cover and create holes for heat to escape. Rain droplets will also add oxygen to the water which will cool down the pool.

        The other weather condition you should be aware of is wind. Pools that get a lot of it may experience less effectiveness when using liquid cover. This is because the wind blows the cover to one side of the pool, leaving a large area of the surface exposed, allowing for heat to escape.

        Does It Work With Salt Pools?

        It doesn’t matter what type of pool you have, you can use liquid solar cover without any issues.

        The cover is pH neutral so it won’t have any adverse effect on your water chemistry or the sanitizers you’re using.

        Whether its a traditional chlorine pool or saltwater pool, liquid solar cover can be used safely and effectively.

        Is It As Effective As Regular Solar Covers?

        Not quite as effective, but it’s pretty close.

        Solar covers are triple-functioning, harnessing sunlight to heat the pool as well as keeping heat from escaping and evaporation from occurring.

        Liquid solar covers don’t harness the power of the sun. They only keep heat from escaping and reduce evaporation.

        They have about 75% effectiveness when compared to a solar blanket. Also, a blanket performs better during inclement weather such as rainstorms and heavy winds.

        How To Use A Liquid Pool Cover

        Now that you know all about them, here’s how you can used liquid solar cover to keep your pool warm:

        Calculate The Amount

        Always consult the manufacturer’s instructions to get the proper dosage for your pool, as how much you’ll need will be determined by the size of your pool.

        A common bottle size you’ll find is 32 ounces. From this bottle, the liquid can provide coverage to a 20,000 gallon pool using only 4 ounces. 

        Pour It Into Your Pool

        Out of all the heating methods, adding liquid solar cover is the easiest and quickest.

        We’d recommend using a measuring cup to measure out the 4 ounces, which translates to ½ cup. You can then simply pour the contents of the measuring cup into the pool and the circulation system will disperse it.

        If you’re using a liquid solar blanket that comes in the form of a pill or toy fish for slow release, it’s best to follow the product instructions.

        Keep It Topped Up

        Like all swimming pool chemicals, liquid pool cover won’t last forever in the water. Depending on how frequently you’re using your pool, you may have to add it more often.

        Generally speaking, with minimal to regular pool use, liquid solar cover should last around one week before needing to be topped up. If you’re using the pool heavily or having lots of parties, you’ll need to add additional liquid cover to maintain its effectiveness.

        Our Top Pick

        Sunheater Shield, 32 oz. Bottle – Liquid Solar Blanket, Non-Toxic and...
        Sunheater Shield, 32 oz. Bottle – Liquid Solar Blanket, Non-Toxic and...
          2 Pack SeaKlear Solar Shield 32oz 90245
          2 Pack SeaKlear Solar Shield 32oz 90245

          Categories: Pool Care, Pool Equipment