Selection guide

Best plastics for water tanks

Rotomoulded HDPE dominates residential and agricultural water tanks — cheap, UV-stabilised, WRAS/NSF-61 approved for potable water, and repairable. PP takes over for hot water and mild chemicals; PVDF and PP-natural for aggressive chemistry.

What to look for

  • NSF-61 / WRAS approval for potable use
  • Stress-crack resistance under permanent hydrostatic load
  • Weathering package (carbon black or HALS) for outdoor UV
  • Rotomouldable in one piece up to the target capacity

Top materials for best plastics for water tanks

  1. #1HDPEHigh-Density Polyethylene

    A rigid, chemical-resistant polyethylene used for bottles, pipes, and industrial containers.

  2. #2MDPE Pipe GradeMedium-Density Polyethylene Pipe Grade

    Good rigidity and stress crack resistance for pipe applications.

  3. #3HDPE Injection MoldingHigh-Density Polyethylene for Injection Molding

    Rigid, strong, and chemically resistant material for crates, caps, and household goods.

  4. #4HDPE Blow MoldingHigh-Density Polyethylene for Blow Molding

    Durable and chemically resistant for bottles, drums, and tanks.

  5. #5XLPE Wire and CableCross-linked Polyethylene for Wire and Cable

    Excellent electrical insulation with enhanced thermal and mechanical properties.

  6. #6CPVC Hot Water PipeChlorinated Polyvinyl Chloride for Hot Water Piping

    Higher temperature and pressure rating than PVC for hot water systems.

  7. #7Chemical Resistant Vinyl EsterVinyl Ester Resin

    Excellent chemical resistance, particularly to acids and solvents, with good mechanical properties.

  8. #8Bio-PE High DensityBio-based Polyethylene, High Density

    A high-density polyethylene produced from renewable sugarcane, chemically identical to conventional HDPE.

  9. #9PEF Barrier BottlePolyethylene Furanoate, Barrier Bottle Grade R

    A 100% bio-based polyester with superior barrier properties to PET, suitable for packaging.

  10. #10Bio-PE Low DensityBio-based Polyethylene, Low Density

    A low-density polyethylene made from sugarcane, offering the flexibility and toughness of conventional LDPE.

  11. #11PETG FDM FilamentPolyethylene Terephthalate Glycol-Modified Filament for FDM

    Durable, impact-resistant, and chemically resistant filament suitable for functional parts and prototypes.

  12. #12rHDPE PCR NaturalRecycled High-Density Polyethylene Post-Consumer Recycled Natural

    Natural colored post-consumer recycled HDPE, suitable for packaging and consumer goods.

  13. #13rHDPE PIR ColoredRecycled High-Density Polyethylene Post-Industrial Recycled Colored

    Colored post-industrial recycled HDPE, suitable for applications where color consistency is key.

  14. #14rHDPE PCR Colored (Blue)Recycled High-Density Polyethylene Post-Consumer Recycled Colored (Blue)

    Blue colored post-consumer recycled HDPE, suitable for industrial packaging and containers.

Frequently asked

HDPE or PP for a rainwater tank?

HDPE. It's cheaper, has better UV packages available and is the standard for rotomoulded tanks up to 30 m³.

Can I use recycled HDPE for potable water?

Only if the specific compound is certified NSF-61 or WRAS. Most recycled HDPE is not.

Values are indicative and vary by grade and manufacturer. Always confirm against the official datasheet before specification.