Evaluating the Performance of Different Water Storage Tank Materials

If the water storage tanks materials is intended for human consumption, the tank material must meet the requirements of the potable-water standard.

New water tanks can sometimes impart distinct flavors and odors. For instance, galvanized tanks may have a metallic taste initially due to excess zinc leaching, and excess lime in new concrete tanks can cause a high pH and possibly a bitter taste. Other types of tanks’ water tend to be slightly acidic.

Plastic (Poly) Tanks


In Australia, the most common type of water storage tanks materials is the plastic or poly water tank, typically manufactured using the rotational molding process. Plastic tanks and plastic liners must be made of materials that are at least food-grade, meeting potable-water standards if used for human consumption.

Polyethylene (Poly) has a long life and is non-corrosive. Polyethylene water tanks will not rust or corrode like metal water tanks over their service life. Poly tanks are lightweight, easy to handle, constructed in a single piece with no joints, and can be recycled at the end of their useful life.

Steel Liner Tanks


Steel liner tanks are steel water tanks with a poly liner that holds the water. The poly liner prevents water from coming into contact with the galvanized, preventing corrosion, and is ideal for storing potable water. If the water is to be consumed, the poly liner material must meet potable-water standards.

Main advantages of steel liner tanks include the liner’s water-holding capacity and the modular steel structure, allowing assembly on-site and being less expensive than comparable-sized concrete tanks.

These tanks are made of galvanized steel, requiring sacrificial anode replacement every 5 years for effective corrosion protection.

Steel Water Tanks


Most water storage tanks materials in previous generations were made of galvanized steel, which has limited corrosion protection. Galvanized steel has a lower corrosion resistance than polyethylene. The introduction of steel tanks with a poly liner is another innovation.

If there is direct contact between the water in the tank and the zinc wall, this may be leached into the tank and can occasionally affect the taste of stored rainwater, but it poses no health risk. Galvanized water tanks should ideally be flushed before use.

Galvanized steel is the primary material used in steel tanks. Galvanizing is the process of applying a zinc-based coating to metal. These galvanized sheets are then soldered together or sealed with a silicon sealant.

Stainless Steel Tanks


Water tanks can also be made from stainless steel, resistant to rust and corrosion, unlike traditional steel tanks. However, stainless steel tanks are significantly more expensive than standard coated steel tanks and plastic tanks.

Concrete Tanks


Concrete and ferro-cement water tanks are extremely strong and long-lasting, typically installed underground. New concrete water tanks may impart tastes and may leach lime, requiring flushing before use.

Concrete water tanks are typically the most cost-effective underground solution, ideal for covering with load-bearing lids and fitting beneath driveways or other structures. One common complaint is cracking and leaking, which can be repaired if the tank can be drained. In some cases, a plastic liner is required.

The concrete tank standard allows for some leakage, whereas the plastic tank standard does not allow for any leakage.



Water can be stored in fiberglass tanks (or GFRP Glass Fiber Reinforced Plastic). The interior surface of these tanks must be coated with a food-grade coating, cured before sale.

Fiberglass has the advantage of being very stiff, allowing relatively thin tank walls to manage water pressure. The disadvantage is that it is brittle and prone to cracking and leaking.

Most fiberglass tanks contain a resin mixed with a catalyst or hardener and glass fibers sprayed onto a mold. Tanks may vary in the manufacturing process, and precautions are needed to prevent algal growth, such as sealing with a black covering inside or painting on the outside.

We offer tried and tested services in Sydney, Melbourne, Brisbane, Canberra, Dalby, Darwin, and Geelong.

Our friendly and experienced customer service team is here to help you! Contact Raven Tanks at 1800 907 834 or [email protected].

Advantages: FiA large metal box with a ladder on top, providing access to its interior. RavenTanks

Fibereglass is also known as GRP (Glass Reinforced Plastic). This material has a number of advantages over other traditional materials used in the construction of water storage tanks. When it comes to installing a modern cold water storage tank, GRP is the ideal material.

1. GRP corrosion resistant

GRP material is the ideal solution for weather-resistant water storage tanks, as it can withstand highly aggressive weather (cold/hot) in comparison to steel, which has low corrosion resistance properties due to oxidation and corrosion, requiring painting or galvanizing. Aluminium tanks corrode as well, necessitating anodizing or other coatings. GRP is also resistant to chemical, wastewater, and sewage corrosion.

2. High strength factor vs alternatives

The superior strength of GRP is far greater than that of equivalent steel profiles. Despite its lightweight nature, GRP has a high strength-to-weight load-bearing capacity. Our GRP products outperform and outlast traditional materials due to the high glass-to-resin ratios used in our technically advanced formulation. Steel must be heavy in order to achieve its high-strength properties. Aluminum does not have this property due to its low strength.

3. Maintenance of GRP

GRP has a design life of 25 years and, due to its corrosion resistance, is maintenance-free when compared to steel and aluminium, which can rust and corrode and must be coated or repainted over the same time period as GRP’s design life. When compared to other traditional materials, GRP is extremely durable and will not distort under impact.

4. Lightweight capabilities vs alternatives

Because of its lightweight capabilities, GRP material is a low-cost option; it is 70% – 80% lighter than steel, and transport costs are dramatically reduced because no heavy lifting equipment is required to on/offload. GRP can be easily moved from the factory to the job site, significantly lowering overall installation costs.

5. Lower production, installation, maintenance & transport cost

GRP material, in comparison to steel and aluminium, has a lower initial material cost but is more expensive to maintain and has a shorter life cycle. The combination of high tensile strength and non-conductive properties results in a highly cost-effective, durable, and sustainable product.

6. Different shapes and colours

GRP tanks can be made in a variety of sizes and shapes, including irregular shapes such as L shapes or tapered shapes. GRP tanks are available in grey or in a specific RAL colour, with popular options including British racing green and blue. Whatever your needs or specifications are, there is almost certainly a GRP tank that will meet them.

7. Modifiable

If you require a truly unique tank, the variability of GRP tanks is not limited to pre-set shapes. All special and standard GRP tanks have standard cut-outs to accommodate connections and fittings, and tanks can be easily cut and drilled with standard plumbers’ tools.

GRP tanks can also be customized to carry a variety of cold water systems and materials: for example, standard specialist GRP tanks can be built to store a variety of chemicals.

8. Accessories available

GRP tank housings and covers are available if you’re particularly concerned about protecting your tank from weather, accidental damage, or vandalism. You can be confident that your tank will be safe with these specially designed enclosures.

Durability: The GRP tanks we offer are square or rectangular in shape and are shipped and delivered in one piece rather than in welded-together components. As a result, they are extremely durable, with no weaker parts such as seals or joins. GRP tanks can be placed indoors or outdoors because they are UV-protected and will not be damaged by prolonged sun exposure.

Sustainability: GRP water tanks are exceptionally eco-friendly. The tanks are made of composite materials to ensure that no harmful chemicals are released while storing water. They have a stainless steel interior that inhibits the growth of bacteria and other organisms that are toxic to humans. When compared to other water storage tanks, the water tanks are lighter in weight and more durable. As a result, they are more cost-effective and efficient to use.

Because of their low maintenance requirements, they are an excellent choice for public spaces and institutions with low water usage. Grp water tanks can be installed both inside and outside. To reduce the amount of air contact with the water, the tanks can be placed indoors. This prevents algae growth in the tank and improves the taste of the water. Furthermore, after being stored in the GRP water tanks, the chlorine in the water is reduced. This renders the water safe to drink without the need for additional treatment.

We offer tried and tested services in Sydney, Melbourne, Brisbane, Canberra, Dalby, Darwin, and Geelong.

Our friendly and experienced customer service team is here to help you!

Call Raven Tanks at 1800 907 834

Or email at [email protected]

Tank & Liner Manufacturers Australia

Are you in need of an industrial water storage solution? We are the leading liquid storage tank & liner manufacturers in Australia, with more than 20 professional years of service behind us.

Having your liquid storage system perform optimally is essential in any industry. Therefore your choice of liquid and water tank manufacturers and maintenance specialist  is paramount to the success of your project & ongoing asset integrity. We offer a wide variety of design, manufacturing, inspection, and maintenance services.

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