Ball Covers vs. Hexagonal Tile Covers — Which Floating Cover Geometry Is Right?

The geometry of a modular floating cover — spherical ball or interlocking hexagonal tile — determines its surface coverage percentage, wind resistance rating, thermal insulation capability, and installation behavior. AWTT manufactures both ball-shaped covers (Armor Ball family) and hexagonal tile covers (Hexprotect and Rhombo Hexoshield families). This comparison provides the engineering data you need to select the right geometry for your pond, tank, or reservoir.

AWTT Engineering · Last reviewed: March 2026 · Technically verified

Why Geometry Matters

Choosing between ball-shaped and hexagonal floating covers is not a cosmetic decision — it is an engineering one. The shape of each modular unit directly affects four critical performance variables:

  • Surface coverage percentage — Spheres cannot tile a flat surface without gaps. Even in the tightest packing arrangement, ball covers leave approximately 9% of the water surface exposed. Hexagonal tiles interlock with minimal gaps, achieving 97–99% coverage.
  • Wind resistance — A sphere's curved profile catches wind differently than a flat-topped hexagonal tile. Self-ballasting hex tiles (like Hexprotect® AQUA) load with water as wind speed increases, creating a progressive anchoring effect that balls cannot replicate.
  • Thermal insulation — Hexagonal tiles can be manufactured with insulating foam cores (R-4 to R-17+), while hollow spheres offer limited insulation (R-2) due to their geometry.
  • Cost per unit of coverage — Ball covers have a lower per-unit cost but require more units to cover the same area due to the gaps inherent in sphere packing.

Where Each Geometry Performs Best

Different site conditions and application requirements favor different cover geometries. Understanding these trade-offs early in the selection process prevents over-engineering sheltered sites and under-specifying exposed ones.

Ball covers are well-suited for:

  • Sheltered ponds and lagoons — Sites protected by berms, tree lines, or buildings where wind is not a primary concern.
  • Budget-constrained projects — When capital cost per square foot is the binding constraint and maximum coverage percentage is not required.
  • Irregularly shaped or obstructed ponds — Spheres flow freely around aerators, mixers, baffles, and other in-pond equipment with no installation adjustment.
  • Temporary or seasonal deployments — Balls can be rapidly poured onto a surface and removed by pumping or netting.

Hexagonal tile covers are well-suited for:

  • Wind-exposed reservoirs and ponds — Coastal, desert, and high-plains sites where sustained winds exceed 35 MPH.
  • Potable water reservoirs — Where 99% surface coverage is needed to block sunlight and suppress algae that produce disinfection byproducts.
  • Heated tanks and digesters — Where thermal insulation (R-4 to R-17+) is required to reduce heat loss and energy costs.
  • Wastewater and odor control — Where high coverage percentage is needed to contain VOC emissions and odors.
  • Applications requiring maximum evaporation reduction — Where every percentage point of coverage translates to measurable water savings.

Side-by-Side Comparison: Ball vs. Hexagonal Geometry

The following table compares ball-shaped and hexagonal tile floating covers across the key engineering and operational criteria that drive cover selection decisions.

Criterion Ball Covers (Armor Ball Family) Hexagonal Tile Covers (Hexprotect / Rhombo)
Surface Coverage % 91% (sphere packing limit) 97–99% (interlocking tiles)
Wind Resistance Sheltered (Armor Ball), 75 MPH (Armor Ball AQUA 275) Sheltered (SLIM), 130 MPH (Rhombo 66), 90+ MPH (Rhombo 189), 130+ MPH (AQUA)
Insulation (R-Value) R-2 (air-filled hollow sphere) R-1 (SLIM), R-2 (AQUA), R-4 (Rhombo 66), R-8 (Rhombo 189), R-17+ (MAX R)
Shape Interlocking None — spheres rest against each other by gravity Tongue-and-groove or nesting geometry — tiles lock together on the surface
Installation Method Pour onto water surface — self-distributing Place tiles onto water surface — self-interlocking
Repair / Replacement Scoop and replace individual balls — seconds per unit Lift and swap individual tiles — minutes per unit
Weight per Unit ~50 g (Armor Ball), ~275 g filled (AQUA 275) Varies by model: 0.3–3.5 kg depending on insulation
UV Protection UV-stabilized HDPE, 25+ year lifespan UV-stabilized HDPE, 25+ year lifespan
Best For Budget applications, sheltered sites, temporary deployments Wind-exposed sites, potable water, insulation, maximum coverage
Key takeaway: Ball covers win on simplicity and cost for sheltered, low-requirement sites. Hexagonal tile covers win on coverage percentage, wind resistance, and insulation — the three variables that drive performance in demanding applications.

Decision Guide: When to Choose Each Geometry

Choose ball covers when:

  1. Your site is sheltered — sustained winds below 35 MPH, with berms or tree lines providing protection.
  2. Budget is the binding constraint — you need basic evaporation reduction and algae suppression at the lowest capital cost.
  3. 91% coverage is acceptable — your application does not require the last few percentage points of surface coverage.
  4. You need rapid deployment and removal — ball covers pour on and pump off faster than any tile system.

Recommended products: Armor Ball® for sheltered sites, or Armor Ball® AQUA 275 for sites with moderate wind (up to 75 MPH).


Choose hexagonal tile covers when:

  1. Wind exposure exceeds 35 MPH — self-ballasting hex tiles provide progressive wind resistance that spheres cannot match.
  2. You need 97–99% surface coverage — for algae prevention, odor containment, or maximum evaporation reduction.
  3. Thermal insulation is required — only hexagonal tiles are available with foam-core insulation up to R-17+.
  4. Potable water certification is requiredHexprotect® AQUA is available in NSF/ANSI food-grade HDPE.
  5. Long-term total cost of ownership matters more than upfront price — higher coverage reduces water loss, chemical use, and energy costs over the 25+ year lifespan.

Recommended products: Hexprotect® SLIM for sheltered high-coverage applications, Hexprotect® AQUA for wind-exposed and potable water sites, Hexprotect® MAX R for maximum insulation, Rhombo Hexoshield® for maximum evaporation reduction + wind resistance, or Rhombo Hexoshield® 189 for high insulation with strong wind resistance.

Why AWTT for Both Geometries

Most floating cover suppliers specialize in a single product geometry — either balls or tiles. AWTT is the exclusive North American distributor of both the Armor Ball family (spherical covers) and the Hexprotect / Rhombo Hexoshield family (hexagonal tile covers). This means our engineering team can evaluate your site conditions objectively and recommend the geometry that delivers the best performance for your specific application — without a bias toward one product line.

Geometry-neutral engineering: AWTT does not push one shape over the other. We recommend ball covers where they are the right fit and hex tiles where they are the right fit. Many of our customers deploy both geometries across different ponds or zones within the same facility. Contact our engineering team for a site-specific recommendation.
  • Full product range — 7 modular floating cover products spanning both geometries, from budget applications to extreme-wind and high-insulation requirements.
  • Site-specific sizing — free volume calculations using our online calculators or direct engineering support.
  • Single-source procurement — one supplier, one purchase order, one point of contact for all floating cover products.
  • 25+ year product lifespan — all products manufactured from UV-stabilized, recyclable HDPE with no maintenance required.

Product Specifications at a Glance

Quick-reference specifications for all AWTT modular floating cover products, organized by geometry. Click any product name for full technical data.

Ball Covers

Product Coverage Wind Rating R-Value Best For
Armor Ball® 91% 35 MPH R-2 Budget applications, sheltered ponds
Armor Ball® AQUA 275 91% 75 MPH R-2 Moderate-wind sites, cost-effective

Hexagonal Tile Covers

Product Coverage Wind Rating R-Value Best For
Hexprotect® SLIM 99% 30 MPH R-1 Lightweight, sheltered high-coverage
Hexprotect® AQUA 99% 130+ MPH R-2 Best all-around, potable water safe
Hexprotect® MAX R 99% 40 MPH R-17+ Maximum insulation, digesters
Rhombo Hexoshield® 98% 95+ MPH R-4 Max evaporation reduction + wind
Rhombo Hexoshield® 189 98% 90+ MPH R-8 Highest insulation with wind resistance

For detailed dimensions, weight specifications, material certifications, and CAD drawings, visit the Technical Data page or contact our engineering team for project-specific documentation.

Frequently Asked Questions

Can ball covers and hexagonal tile covers be used on the same pond?

Yes. Ball covers and hexagonal tile covers are independently buoyant and can be deployed in separate zones of the same water body. For example, you might use Hexprotect AQUA tiles in a wind-exposed section for maximum wind resistance and Armor Ball units in a sheltered cove where budget is the priority. The two geometries will not interlock with each other, but they will butt up against one another and still provide effective coverage across the full surface.

Which geometry is better for windy sites?

Hexagonal and hybrid tile covers outperform ball covers in high-wind environments. The Hexprotect AQUA tile is rated to 130+ MPH through self-loading water ballast, and the Rhombo Hexoshield 66 achieves 130 MPH through water-ballasted hybrid geometry. The Rhombo Hexoshield 189 handles 90+ MPH sustained winds. By contrast, the best-performing ball cover — Armor Ball AQUA 275 — is rated to 75 MPH.

Are ball covers cheaper than hexagonal tile covers?

On a per-unit capital cost basis, Armor Ball spheres are typically the lowest-cost modular floating cover option in the AWTT range. However, hexagonal tiles achieve higher surface coverage (97-99% vs. 91%), which means fewer units may be needed to reach a target evaporation reduction. When evaluated on a cost-per-percent-of-evaporation-reduced basis, hexagonal tiles often deliver comparable or better value, especially when wind resistance and insulation are factored into the total cost of ownership.

Do hexagonal covers require more maintenance than ball covers?

No. Both ball covers and hexagonal tile covers are manufactured from UV-stabilized HDPE with no moving parts, no fasteners, and no mechanical components. Neither geometry requires routine maintenance over its 25+ year expected lifespan. If a unit is damaged, it can be individually removed and replaced without draining the pond or disturbing surrounding units — regardless of whether the cover is ball-shaped or hexagonal.

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