In The Swim 20 ft x 40 ft 12 Mil Blue Rectangle Solar Pool Cover

In this review the In The Swim 20 ft x 40 ft 12 Mil Blue Rectangle Solar Pool Cover is assessed for pool owners who want an economical way to extend swimming season and reduce heat loss. The bottom line: this cover is best for owners who want a simple, effective solar heating aid that raises surface water temperature and prevents evaporative heat loss at night. It is a straightforward, durable-feeling sheet that delivers measurable warmth without the complexity of a mechanical heater.

Key Features

• 12 Mil thickness: Thicker material helps increase surface water temperature by up to 15 degrees for more comfortable swimming and longer season use.
• Light blue color: The medium blue balance absorbs and retains heat while still allowing some light transmission to avoid overheating and encourage gentle warming.
• Evaporation control: The cover reduces evaporative heat loss overnight, which helps keep pool temperature stable and cuts replenishment of water due to evaporation.
• Chemical guidance: Designed to be used when chlorine is below 2.5 ppm and pH is above 7.2 to avoid premature degradation from high chemical exposure.
• Compatible with reels: The cover works with a solar cover reel for easier removal and application, reducing manual handling wear and tear.

Who It's For

The cover suits above ground and inground pool owners who want a low-cost method to raise and retain water temperature without installing a heater. It is ideal for those who swim in transitional seasons or who want to cut heating costs by making solar gains more effective.

It is less appropriate for owners who run very high chlorine levels or very low pH, since the manufacturer recommends using the cover only when chlorine is under 2.5 ppm and pH above 7.2. Those seeking a permanent, professional heating system should look elsewhere.

Pros & Cons

Pros

• Provides noticeable warmth, with customers reporting consistent comfort gains and surface temperatures several degrees higher.
• Good value compared with active heating; simple trimming and installation make it accessible for most owners.
• 12 Mil material feels substantial and resists tearing during routine handling when used with a reel.

Cons

• Longevity is mixed in customer reports; some users see several years of life while others report earlier wear depending on care and chemical balance.

Specifications

Product type	Rectangle solar pool cover
Size	20 ft x 40 ft
Thickness	12 Mil
Color	Light blue
Compatible pools	Above ground and inground pools
Chemical guidance	Use when chlorine < 2.5 ppm and pH > 7.2

Our Verdict

The In The Swim 20 ft x 40 ft 12 Mil solar cover is a practical, good-value choice for pool owners who want measurable warmth and reduced evaporation without complex equipment. It performs best when stored and handled with care and used within the recommended chemical ranges, delivering an economical way to extend your pool season.

Frequently Asked Questions

Will this cover fit my rectangular pool?
It is sized 20 ft x 40 ft so it will fit pools of that size or slightly smaller after trimming; many users trim the edges for a precise fit.

Can I leave the cover on at night?
Yes, the cover is intended to prevent overnight evaporative heat loss and help retain warmth; follow the chemical guidelines for best life.

Do I need a reel to use this cover?
A reel is not required but highly recommended because it makes application and removal easier and reduces wear from handling.