When it comes to heating your pool, the first solutions that enter most peoples' minds are heaters/heat pumps or traditional solar blankets. And both of these are great solutions ... if you have the budget for them or want to do extra work.
How to Keep Your Pool Warm
Swimming pool heaters and heat pumps do a great job of warming up your pool. But they're expensive to buy, and expensive to operate, which puts them out-of-reach for many pool owners.
Solar blankets (the covers that kind of look like bubble wrap for your pool) are considerably less expensive than heaters, and do a fantastic job using the sun's rays to heat your pool water. But they have to be taken off the pool every time you want to swim and put back on once you're done (in order for them to do their job).
There is, however, a third, low-cost, alternative that not only works in pretty much any kind of swimming pool, requires barely any effort, and is completely safe: liquid solar blankets.
What Are Liquid Solar Blankets?
Liquid solar blankets are an ultra-thin, invisible layer of alcohol that floats on top of your swimming pool water, minimizing evaporation and heat loss.
The liquid can be added directly to your pool, though a more effective (and easier to maintain) solution is through the use of timed-release distributors, such as the Solar Ball. Just follow the directions, drop the appropriate dosage of Solar Balls (one ball per 400 square feet of pool surface) into your skimmer basket, and you'll be set for about a month.
How Do Liquid Solar Blankets Work?
The majority of heat loss in your pool is due to evaporation of pool water. This is one of the major reasons covers can help keep your pool warmer.
Liquid solar blankets keep heat in your pool in much the same way as a cover would. The invisible barrier they create on the surface of your water minimizes evaporation, which means warm water stays in your pool rather than disappearing into the atmosphere.
Are Liquid Solar Blankets Safe?
Liquid solar blankets are absolutely safe, for both children and pets. In fact, the alcohol used in them is biodegradable, so they're even safe for the environment. Still, the liquid in a liquid solar blanket should never be ingested undiluted, straight from the container.
One additional "safety feature" versus a traditional plastic solar blanket, is that with a liquid solar blanket you can even swim while you're cover is "on." Since the alcohol has a lower density than water, the liquid blanket will just mix in with the water while you're swimming, then float back up to the top and get back to work when the water settles.
Do Liquid Solar Blankets Work with my Cleaning System?
Liquid solar blankets are made with swimming pools in mind, which means they will work with your pumps, filters and even automatic cleaners. One tip to encourage the best results from your liquid solar blanket: make sure your return jets are pointed sideways or downward as having them point upwards can disturb the surface of the water, making evaporation more likely.
Do Liquid Solar Blankets Work in Mineral or Saltwater Pools?
You can use liquid solar blankets in any type of swimming pool. Chlorine, saltwater, mineral water ... vinyl liner, concrete or fiberglass. They're safe for all.
I Already Have a Heater. Why Would I Want a Liquid Solar Blanket?
Remember when we explained how liquid solar blankets work by reducing evaporation in your pool? Well that means that with a heated pool, you're losing less of your heated water to evaporation as well. That thin protective layer from the liquid blanket prevents the warm water from evaporating, which means your heater will not have to work nearly as hard to keep the pool warm. And as an added bonus, with less evaporation you most likely won't have to add water or chemicals to your pool as often!
Will a Liquid Solar Blanket Heat My Pool?
No, a liquid solar blanket will not heat your swimming pool. A liquid solar blanket works more like insulation, meaning the heat that's in the pool (from the sun, your heater, etc) doesn't dissipate as quickly, so your water stays warmer even as the air temperature drops. If you're looking to add heat to your pool, a traditional solar cover (the kind that looks a lot like bubble wrap), will also help trap heat and reduce evaporation, but actually warms your water by magnifying the sun's rays as well (something a liquid solar blanket does not do). 
While liquid solar blankets trap heat or reduce water evaporation, a traditional solar is much more effective at this, though you can expect your water temperature to stay about five degrees or so warmer by using a liquid solar blanket versus nothing at all.
If you are looking for a way to actually raise the temperature of your pool water we highly recommend adding a traditional solar blanket (ideally with a cover reel, not only for simple storing but to make it easier to take on and off with ease). A traditional solar cover will help heat your pool water, though it does rely on the sun to do so. Meaning, no sun...no heat. For maximum heating capability, you'll really want to invest in a heater or heat pump (see this difference here). A heater or heat pump will be effective any time of day, any time of the year, and in any weather.
It all comes down to your goals and your budget. The good thing is, any of these can be added to an existing pool at any time. So if you are looking for a quick fix to fluctuating temperatures, a liquid solar blanket may be a good place to start. But if you want a warm, spa-like pool experience, get a solar blanket (or better yet, a heater or heat pump) then add a liquid solar blanket to keep all of that glorious warmth inside of your swimming pool.
Should I Get a Liquid Solar Blanket?
A liquid solar blanket is very effective when paired with other swimming pool heating elements as they are quite helpful in retaining heat in your pool. They're fairly inexpensive, very easy to use, and most importantly safe.
If you are looking for something quick, easy, and inexpensive way to keep heat in your pool (and save time and money on other maintenance like adding water or chemicals) liquid solar blankets are definitely a good place to start. Happy Swimming!
