20,000 Gallon Tank

Please call Eco Products Maui for pricing: 1 (808) 878-6762


The 20,000 gallon system provides 10,000 gallons of water to meet the needs of a family of four for one month, plus an additional 10,000 gallons of reserve storage for one month of serious drought. This system is usually large enough to support a garden between rains.

Package Details

Tank Frame

  • Capacity: 20,000 gallons
  • Dimensions: 21′ 7″ diameter by 7′ 2″ height
  • Galvanized Metal Tank Frame: The corrugated metal framework is triple-coated, galvanized hardened steel used in culverts that are made to be in contact with earth and water. All hardware fasteners are also triple-coated, hot-dipped, galvanized hardened steel. The hardened galvanized steel is 18 gauge according to engineering specifications issued by the USDA for various water tank diameters and heights.
  • Galvanized Tank Hardware: Nuts, bolts, and washers
  • Long Term Protection: Prep, galvanized primer, and exterior paint provide long term protection inside and out with Gripper Galv. metal primer – one coat inside and two coats outside of quality exterior enamel. Prep materials, primer, and exterior enamel are included in this tank kit.
  • Foundation Base Bricks: Cement bricks (2″ x 8″ x 16″) are used under the water tank frame to provide a level solid base for the tank and to raise it above ground level.

Liner and Cover

  • Reinforced HDPE Liners: Custom made from high density polyethylene (HDPE), FDA and NSA approved for drinking water and very resistant to ultraviolet (UV) damage. Unlike conventional vinyl, HDPE does not shrink or get brittle and crack over time. The molecules in high density polyethylene fabric are tightly knit which has the advantage of light weight relative to strength. Black HDPE liners are much more resistant to sun damage and remain more flexible over time than single layer low density fabrics like vinyl whose molecules create taste and smell in the water. Our patented, reinforced, HDPE tank liner fabric is exceptionally strong because it is made like plywood with layers in opposite directions. The fabric includes a mesh layer of nylon every 1/4″ in both directions which substantially increases the burst and tear strength. Reinforced HDPE liners have exceptional durability and commonly have a service life of 15 to 20 years in Hawaii.
  • Premium Mesh Cover with Flat Cover Support System: This tank system includes our Premium Mesh Cover with Flat Cover Support System. The Premium Mesh Covers are sewn with a reinforced hem and solid brass grommets for the installation. The Flat Cover Support System for this size tank uses two lines of vinyl-covered aircraft cable across the top of the tank that are attached to the side of the tank with stainless steel turnbuckles, etc. This cable system is designed to keep the cover from excessive sagging and preserve its longevity. Eco Products Maui also offers other types of cover support systems. See Water Tank Covers.


  • S-80/Brass Plumbing Kit: Includes all necessary pipes, fittings. and the valve control box. We recommend, supply, and install the best quality plumbing parts available. This plumbing kit goes from the exit at the bottom of the tank to a 1.5” brass ball valve in a valve control box just outside the tank. The purpose of this plumbing kit is for the water supply to the pump.
  • Basic Overflow System: The overflow system provided in this package consists of two 1.5” PVC pipes that run from the top of the tank down to the ground on the tank exterior and terminate away from the foundation. Depending on roof size and rainfall, this overflow system doesn’t keep the tank from overflowing during times of intense rain. Eco Products Maui offers larger overflow systems (see Rain Catchment Systems) that can handle intense rain without overflowing.

What’s Not Included

Since the site of the tank and water system varies from one location to another, parts of the water system that are outside of the tank must be specifically designed and implemented accordingly.

As a result, the following is not included in the price of the water tank kit:

  • Pipes and fittings for the outside of the tank to the domestic house/building supply.
  • Pipes and fittings from the house gutters down to the ground and underground to the tank to the “stub outs” at the tank.
  • Site preparation, gravel and sand for tank foundation. (See Site Preparation.)
  • Labor costs for installation.
  • Freight and delivery to the site by Young Brothers.


Once the water tank site is properly leveled and graveled, a team of installers can erect the water tank’s metal framework in one day. On another day, it can be painted by Eco Products Maui or the owner. On a third day, the liner, tank exit plumbing, cover, and overflow system can be installed and the supply to the tank can be completed. The optional EcoClean rainwater harvesting system, and any of our pump systems, are installed after the liner is installed and before the cover is done. Labor costs can be accurately known in advance.


  • A level, 24+’ diameter, properly prepared site. (See Site Preparation.)
  • When the tank is completed, water is needed to seat and test the tank liner.

Pricing, Planning and Design Consultation

Please Contact Us at Eco Products Maui for more information.