Liquid Solar Swimming Pool Covers

Reduce your pool's heat loss and evaporation without the hassle of a physical blanket with a liquid solar pool cover. Liquid covers form an ultra-thin, transparent molecular layer on the water's surface that significantly reduces evaporation and retains solar heat — while remaining completely invisible and safe for swimmers. PST Pool Supplies stocks liquid pool cover products from Flexible Solutions (Heatsavr), AquaPill, CoverFree, and Pro Series, with individual doses starting from under $3.

Heatsavr by Flexible Solutions is the leading liquid solar cover on the market — backed by independent testing showing up to 30–40% reduction in evaporation and measurable heating cost savings. Available in everything from 2-pack 32-ounce bottles for small pools to 5-gallon pails for commercial use, Heatsavr works by dose-and-forget application: add to the pool weekly or pair with the HS115 or HS230 Automatic Metering System for hands-free, timed dispensing. The automatic metering system mounts at the pool edge and dispenses precise micro-doses at set intervals — ideal for pools where manual weekly dosing is impractical. AquaPill liquid solar blankets (available in 12,000-gallon #73 and 30,000-gallon #72 formulations) use a similar molecular barrier chemistry and dissolve gradually from a capsule form. CoverFree and the Pro Series Liquid Cover are complementary options for pools of different sizes and budget requirements. For physical pool covers and solar blankets, see our pool cover collection. Independent studies on liquid pool cover effectiveness have been published by the U.S. Department of Energy.

Liquid pool covers are especially valuable for pools where a standard solar blanket is impractical — irregularly shaped pools, pools with features like waterfalls or fountains that would damage a blanket, pools that are used frequently throughout the day, or pools without dedicated storage space for a bulky cover. They are compatible with all sanitization systems including chlorine, bromine, saltwater, and ozone systems. The molecular film is broken up during swimming and re-forms within minutes after activity stops. Liquid covers do not replace physical winter covers for cold-climate pool closings, but provide significant energy savings as a season-long supplement to regular pool heating. Dosing frequency depends on pool volume, water circulation, and wind exposure — follow the product's dosage guide for best results.

Shop liquid solar pool covers and start saving on pool heating costs without the effort of managing a physical blanket.