A solar pool cover can reduce evaporation and slow heat loss when it covers most of the water surface. It is not a powered heater, a substitute for sanitation, or a safety cover. This guide compares seven commonly searched bubble covers and explains how to choose by pool dimensions, handling, thickness, color, and verified listing details.
Before ordering or cutting a blanket, use our solar-cover measurement and handling checklist to plan around the waterline, obstacles and reel. Remove the cover completely before swimming; a bubble blanket is not a safety cover.
How this guide was prepared: This is a research-based comparison, not a hands-on product test. We reviewed U.S. EPA water-efficiency guidance, U.S. Consumer Product Safety Commission warnings, product listings, and available manufacturer information. Product dimensions, availability, and warranty terms can change, so verify the exact listing before purchase. Research was updated September 16, 2026.
Affiliate disclosure: Some links are affiliate links. Temperature Master may earn a commission at no extra cost to you. Affiliate relationships do not change the selection criteria below.
Critical safety note: A bubble-style solar blanket is not a safety cover and must not replace a code-compliant barrier or an ASTM F1346-compliant safety cover. Remove the blanket completely before anyone enters the pool. Never swim under or near a partially removed solar cover, and keep children away from the pool and cover unless actively supervised.
What a solar cover can—and cannot—do
EPA WaterSense describes pool covers as the most effective way to reduce evaporation. Its residential guide reports that solar bubble covers, rings, and thermal covers can reduce evaporation by roughly 50% to 95% while in use, depending on their shape and how much of the surface they cover. Results vary with wind, humidity, water temperature, climate, fit, and how consistently the cover is used.
- Evaporation: better surface coverage generally means less exposed water and lower evaporative loss.
- Heat: a cover mainly helps by limiting evaporative cooling and retaining heat already in the water. Sunlight may add heat, but no responsible guide can promise a fixed temperature increase for every pool.
- Chemicals: reducing water loss can reduce refill demand and may reduce some chemical demand, but the cover does not sanitize water. Continue testing and balancing the pool.
- Debris: a blanket may intercept some leaves and dirt, but it is not a winter cover or load-bearing cover.
If you are trying to distinguish normal water loss from a leak, start with our guide to how much pool evaporation is normal. If your goal is faster or more predictable heating rather than heat retention alone, compare the operating tradeoffs in our gas vs. electric pool heater guide.
Quick comparison
| Cover | Research use case | Verify before buying |
|---|---|---|
| Sun2Solar Blue 1200 Series | General-purpose blue bubble cover | Exact pool size, 12-mil listing, trimming and warranty terms |
| Intex round solar cover | Compatible round above-ground pools | Pool model and inside diameter; drainage-hole design |
| Blue Wave NS525 clear | Large clear 14-mil listing | 18 x 36 ft listing, actual cover dimensions and current warranty |
| Steinbach Krystal | Small round-pool option | Metric/imperial dimensions and supported pool diameter |
| Blue Wave NS445 blue | Large rectangular pool | 20 x 44 ft listing, weight, reel compatibility and warranty |
| In The Swim Basic 8 Mil | Lighter large rectangular cover | 20 x 40 ft listing and current trim/warranty instructions |
| Sun2Solar Clear 1200 Series | Clear 12-mil alternative | Exact dimensions, reel fit and current warranty terms |
How to choose a solar pool cover
1. Measure the water surface
Measure the pool’s maximum length and width—or inside diameter for a round pool—and compare those measurements with the manufacturer’s instructions. Some bubble covers are intended to float inside the pool perimeter and be trimmed to the waterline; others are pre-shaped for a particular above-ground pool. Do not assume every cover should overlap the deck or pool wall. Follow the exact brand’s trimming directions so the cover remains manageable and does not interfere with skimmers, rails, or fittings.
2. Read mil correctly
Bubble covers are commonly sold as 8-mil, 12-mil, or 14-mil products. A mil is one-thousandth of an inch; it is not a millimeter. The original version of this article incorrectly labeled these products as 8 mm, 12 mm, and 14 mm. A thicker listing may feel more substantial and may be easier to use with a reel, but thickness alone does not prove better heating, durability, or evaporation control.
3. Treat color claims cautiously
Clear, blue, and darker covers transmit and absorb sunlight differently, but real pool performance depends on more than color. Cloud cover, shade, wind, nighttime temperatures, water chemistry, surface coverage, and use pattern all matter. Choose color together with verified material, size, ease of handling, and manufacturer instructions—not a universal promise such as “15 degrees in one day.”
4. Choose a cover you will actually use
EPA notes that a cover only saves water while it is on the pool. A heavy cover that is difficult to deploy may be used less often. For a large pool, consider a compatible reel and enough clear space to remove and store the blanket completely before swimming. Protect the removed cover from concentrated sunlight and follow the manufacturer’s cleaning and storage directions.
Research pick: Sun2Solar Blue 1200 Series
This blue 12-mil listing is a practical general-purpose candidate because it is sold in multiple rectangular sizes and is intended to float bubble-side down. The product should be chosen by the pool’s actual water-surface dimensions, not by a generic “fits almost any pool” claim.
The blue cover may be trimmed only if the current Sun2Solar instructions and warranty allow it for the exact SKU. Confirm those terms before cutting. Do not rely on a fixed 95% evaporation or temperature-increase promise for this individual product; EPA’s broader 50% to 95% range for solar covers depends heavily on coverage and use.
- Strengths: widely available sizing, 12-mil construction in the reviewed listing, and a familiar bubble-down format.
- Limitations: large sizes can be cumbersome without a reel, and durability or warranty claims must be confirmed from the current seller/manufacturer terms.
Round above-ground option: Intex Solar Cover
The Intex Solar Cover is shaped for specific round above-ground pools. This is more important than the brand name: match the listed cover diameter to the pool’s inside diameter and model. A smaller inside-floating cover can be intentional, so it should not be stretched over the pool wall unless Intex’s instructions say to do so.
Drainage holes can keep rainwater from pooling on top, but they also mean this is not a solid debris cover and not a safety cover. Check the current listing for the included storage bag, exact dimensions, supported pool series, and care instructions.
- Strengths: pre-shaped round format and lightweight handling for compatible above-ground pools.
- Limitations: compatibility is model- and diameter-specific; drainage holes and uncovered edges may reduce evaporation control compared with full coverage.
Clear 14-mil option: Blue Wave NS525
The Blue Wave NS525 listing reviewed for this guide is a clear 14-mil blanket marketed for an 18 x 36-foot rectangular in-ground pool. It is a heavier option for buyers who prioritize a thicker clear blanket and can manage its size.
Do not interpret 14 mil as 14 mm—the difference is more than two orders of magnitude. Also verify the current warranty, whether trimming is permitted, the true material dimensions, and the recommended reel. The previous article’s promise of a 15°F increase is not retained because weather and pool conditions vary too widely.
- Strengths: clear material, thick 14-mil listing, and size aimed at a common large rectangular pool.
- Limitations: weight and handling; current warranty and trimming rules require verification.
Small round-pool option: Steinbach Krystal
The Steinbach Krystal Solar Cover is a small round bubble cover whose listing uses both metric and imperial measurements. Confirm the cover’s actual diameter and the pool size it is designed to fit; those two measurements are not necessarily identical.
This option should not be layered with separate loose covers. Multiple floating pieces can be harder to remove quickly and can create additional entanglement hazards. Use one correctly sized cover, remove it fully before entry, and follow the manufacturer’s storage directions.
- Strengths: compact size and lighter handling for a compatible small round pool.
- Limitations: limited size range and marketplace details that should be verified carefully.
Large rectangular option: Blue Wave NS445
The Blue Wave NS445 listing targets a 20 x 44-foot rectangular in-ground pool and uses 12-mil blue material. Its main advantage in this comparison is size, not a guaranteed heating result.
Large bubble blankets become heavy and awkward when wet. Confirm reel compatibility, storage space, actual cover dimensions, trimming permission, and the current limited-warranty exclusions before purchase. A cover that is too difficult to deploy consistently will deliver fewer evaporation savings.
- Strengths: one-piece coverage for a large rectangular surface and 12-mil listing.
- Limitations: higher weight, price, and handling demands; no universal 15°F claim.
Lighter large-cover option: In The Swim Basic 8 Mil
The reviewed In The Swim Basic listing is an 8-mil, 20 x 40-foot rectangular bubble cover. It may be easier to handle than thicker material of the same size, which can matter more in daily use than a nominal thickness comparison.
Confirm the current size, seam design, trimming instructions, warranty, and expected service life from the seller or manufacturer. The original article made unsupported claims about a three-year warranty, multi-year lifespan, and a 10°F increase; those claims have been removed.
- Strengths: lighter 8-mil format and a large rectangular size.
- Limitations: thinner material may be less resistant to handling damage; verify current warranty and care requirements.
Clear 12-mil alternative: Sun2Solar Clear 1200 Series
This clear 12-mil Sun2Solar listing is an alternative for buyers who prefer a clear blanket. It should be evaluated by exact dimensions, handling, storage, reel compatibility, and current manufacturer instructions—not by a promise of “rapid heating.”
Clear material can transmit more sunlight than an opaque cover, while the blanket also reduces evaporative cooling. The net temperature change still depends on weather, shade, wind, water temperature, pool mass, coverage, and nighttime conditions. Remove it completely before any swimmer or robotic cleaner enters the pool.
- Strengths: clear 12-mil construction in the reviewed listing and multiple advertised sizes.
- Limitations: no responsible one-day temperature guarantee; verify cutting and warranty terms before trimming.
Safe use and care
- Remove the solar blanket completely before swimming, servicing the pool, or running a cleaner that is not explicitly approved for use under a cover.
- Never allow a child or adult to walk, crawl, or play on a bubble cover. It is not load-bearing.
- Keep the pool protected by the barriers, alarms, gates, and safety-cover requirements in your local code.
- Use the cover only when water chemistry is within the manufacturer’s permitted range. Follow any instructions about removing it after shock treatment.
- When removed, store it as directed and protect it from concentrated sun and heat, which can damage bubble material.
- Replace a cover that is brittle, delaminating, shedding plastic, or difficult to remove safely.
Bottom line
The best solar cover is the correctly sized cover that is easy enough to use consistently and remove completely before swimming. Sun2Solar’s blue 12-mil listing is the general research pick here, while the Intex option may suit a compatible small round above-ground pool and the Blue Wave models address larger rectangular surfaces. Treat all temperature, durability, and warranty claims as model-specific and confirm them before purchase.
Sources and update notes
- U.S. EPA WaterSense: Jump Into Pool Water Efficiency
- U.S. EPA WaterSense: Home Maintenance—Pools
- U.S. CPSC: Drowning Hazard Warning for Solar Pool Covers
Updated September 16, 2026: Rebuilt the article as a disclosed research comparison; corrected mil versus millimeter errors; removed unsupported universal temperature, durability, warranty, and evaporation claims; added EPA-backed evaporation guidance and prominent CPSC safety guidance; removed unverifiable first-person experience language.
