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Dometic 20 HTS-HRZ Basic Series Waste Water Holding Tank System - 18 Gallon

Dometic 20 HTS-HRZ Basic Series Waste Water Holding Tank System - 18 Gallon

  • Capacity: 18 Gallons, Dimensions: 14" x 14.25" x 28.25"
  • Orientation: Horizontal, Material: Odor Free High-Strength Polyethylene
  • Includes (3) 1-1/2" Fittings and 5/8" TankSaver Relief valve
  • Item #: 
    Dometic(formerly SeaLand)
    Model #: 


    Shipping Weight: 
    34.79 Lbs.
    List Price: 
    Reg. Price:
    Sale Price:
    Status:   null Call to confirm

    Quantity : 

    Shipping weight reflects calculated Dimensional Weight and is not actual product weight - see here for details.

    Complete, reliable holding tank systems for use with marine toilets.
    Virtually any boat with room for a holding tank can now incorporate the advantages of Dometic’s premium-quality Holding Tank Systems.

    Leak-proof Design- Top-mounted hose connections eliminate standing liquid in discharge hose, preventing odor permeation through hose.

    Odor-free, Highly Durable Tank- 100% virgin polyethylene resin with extra-heavy wall thickness prevents odor permeation and resists corrosion.

    Implosion Protected- TankSaver® vacuum relief valve prevents damage from dockside pumps that use very high levels of vacuum.

    ISO/USCG Compliant- Dometic holding tanks fully comply with the ISO 8099:2000(E) standard and applicable U.S. Coast Guard requirements.

    System Features:

    • Heavy-duty 3/8" polyethylene
    • TankSaver® relief valve
    • Inspection port
    • Inlet
    • Vent outlet
    • Two discharge outlets


    • Tank capacity: 18 gal. (68 L)
    • Empty weight: 27 lbs. (12.2 kg)
    • Full weight: 178 lbs. (80.7 kg)
    • Inlet fitting size: 1-1/2 in. (38.1 mm)
    • Outlet fitting size: 1-1/2 in. (38.1 mm)
    • Vent outlet size: 5/8 in. (15.9 mm)
    • Dimensions: 14"H x 14.25"W x 28.25"D Horizontal Style

    NOTE: HTS-Basic Series holding tank systems do not include pumps. Pump is Sold Separately.


    Dometic DTM01 Holding Tank Monitor
    Item #: 501421
  • Monitors Level in (1) Waste Holding Tank - with Full Tank Alert
  • Power: 12 / 24 Volt DC, Includes (1) 1-Level Probe Assembly
  • Cutout: 1" dia., Dimensions (Panel): 3-1/4" x 2"
  •  Include
    Reg. Price

    Sale Price

    Model #:
    Dometic OdorSafe Hose Plus - 1-1/2 Inches
    Item #: 502434
  • Diameter: 1-1/2" ID, Color: White
  • Material: PVC Reinforced with PVC Helix, Tolerance: 270 PSI
  • Sold by the Foot, ( 50 feet Maximum Continuous Length )
  •  Include
    Model #:
    Dometic ECO Holding Tank Vent Filter Kit
    Item #: 503469
  • Applications: Replaces all Previous SeaLand and Dometic Vent Filters
  • Includes: Mounting Brackets and Hose Fitting Adapters for All Size Vent Hoses
  • Annual Filter Replacement Recommended
  •  Include
    Reg. Price

    Sale Price

    Model #:
    Dometic Universal Holding Tank Cleanout Kit
    Item #: 753760
  • Applications: Installs Easily on Any Rigid Holding Tank
  • Includes 3" Inspection Port, Cap, O-Ring, Gasket and Stainless Hardware
  • Function: Provides Easy Access to Tank Interior for Inspection / Cleaning
  •  Include
    Model #:
    Dometic Holding Tank Diptube Kit
    Item #: 502436
  • Function: Prevents Clogging and Minimizes Tank Residual
  • Applications: Tanks Up To 30 Inches Deep
  • Cutout: 3"
  •  Include
    Reg. Price

    Sale Price

    Model #:
    Forespar Replacement Waste Deck Fill
    Item #: 300826
  • Type: Waste, Includes Nylon Retainer Cord, Color-Coded Black Cap (Keyed)
  • Material: Marelon, Extra Large Flange Diameter: 4"
  • Hose Barb Diameter: 1-1/2" OD
  •  Include
    Model #:
    Whitecap Tank Vent with Wire Screen
    Item #: 300829
  • Includes Screen Flame Arrestor, Material: 316 Stainless Steel
  • Hose Size: 5/8", Hole Cutout: 3/4"
  • Applications: Commonly Used on Fuel Tanks but Works to Vent Any Tank
  •  Include
    Model #:
    Whitecap Fuel Tank Vent with Wire Screen
    Item #: 300830
  • Type: Angled (90 Degrees), Material: 316 Stainless Steel
  • Applications: 5/8" Inside Diameter Hose, Hole size is 3/4"
  • Commonly Used on Fuel Tanks but will Vent Any Tank
  •  Include
    Model #:
    Dometic Max Control Advanced Holding Tank Deodorant
    Item #: 753911
  • Odor Control Formula also Breaks Down Waste and Toilet Tissue
  • Mix Ratio: 4 ounces per 40 Gallons of Holding Tank Capacity
  • Package: 6 Ounce Contains (3) 2 Ounce Pouches, Concentrated Formula
  •  Include
    Model #:

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