Solar Cover vs Liquid Solar Blanket: Which Saves More?

Both solar covers and liquid solar covers reduce evaporation and chemical loss, but they work differently and cost differently. If you’re trying to decide between wrestling a physical cover on and off every weekend or adding a chemical to your skimmer once a week, here’s the side-by-side breakdown.

Physical solar cover (the bubble blanket)

How it works: a sheet of bubble-textured polyethylene floats on the water surface. Sunlight passes through and heats the water; the bubbles trap heat against evaporation and night-time cooling.

Cost: $80–$300 depending on pool size. Plus $100–$300 for a reel to make on/off easier.

Lifespan: 3–5 years.

Evaporation reduction: 50–70%.

Heat retention: raises water temperature 5–10°F over uncovered.

Pros: highly effective; pays for itself in 1–2 years through chemical and water savings.

Cons: requires physical handling (10+ minutes to put on and take off). Reel takes deck space. Heavy and unwieldy on larger pools.

Liquid solar cover (the chemical)

How it works: a microscopic alcohol-based monomolecular layer forms on the water surface. Invisible. Reduces evaporation at the molecular level.

Cost: $20–$40 per quart, lasts 4–6 weeks per dose.

Lifespan: use continuously throughout swim season.

Evaporation reduction: 15–40%.

Heat retention: raises water temperature 1–3°F over uncovered.

Pros: no physical cover to manage. Use a salt pool or freshwater pool. Works while you swim. Compatible with any sanitizer system.

Cons: less effective than a physical cover. Slightly increased cost over the season. Some users notice a thin film at the waterline.

Liquid solar options at PST

Which is right for you?

• Use a physical solar cover if: you have a smaller pool (under 18x36), you want maximum heating, and you don’t mind the daily on/off routine.
• Use a liquid solar cover if: you have a large pool, you swim every day (physical covers are inconvenient), or your pool is in an open landscape where deck space for a reel is limited.
• Use both: physical cover at night for maximum savings; liquid daily for convenience when the pool’s in use.

Both pay for themselves through chemical and water savings if used through the swim season. Send PST Pool Supplies your pool size and use pattern, and we’ll match the right product.