Selecting The Most Cost-Effective Rainwater Tank Size That Suits Your Requirements

The cheapest rainwater tanks are a viable and practical investment for families and communities that harvest rainwater. They help exploit other benefits of rainwater, such as its low harvesting costs and the unlimited free water supply during rainy seasons. There are factors to consider in the economics of finding the cheapest rainwater tank size.  Rainwater harvesting, as the casinos 20Bet, is legal in almost all countries.

Which is the Cheapest Rainwater Tank Size?

Although the price of a water tank depends on its size, other factors such as material and utility matter. There are guides on the appropriate tank size depending on the following:

Number of Intended Water Consumers

Often, sellers range tank size capacity on the family size or the number of people in a household. That determines the average water consumption to ensure a consistent water supply. A family of 4 needs a water tank of at least 15,000 liters of storage capacity. 

Different suppliers stock water tanks with over 40,000 liters of capacity to suit diverse storage and consumption needs. Some suppliers have online water consumption calculators to help buyers estimate the appropriate water tank sizes. 

Buyers should also consider other intended uses of the water, such as livestock rearing and farming, beyond domestic consumption.

Water Tank Materials 

Concrete, steel, and polyethylene are common materials used to make rainwater tanks. Poly tanks are easy to ship and install. They come in many colors, sizes, and shapes, which makes them versatile for different installations. 

The best type is the food-grade quality approved for holding drinking water. They are durable tanks with a guarantee of over 20 years.

Concrete tanks are often installed underground, making them a suitable choice where there is limited space for installation. They are rigid but durable. However, concrete tanks are a time-consuming, labor-intensive, and costly option for installation. 

Steel water tanks are metal tanks fabricated from galvanized steel or zincalume. They are robust and fit both above-ground and below-ground installations. Due to corrosion risk, most metal tanks have polyethylene lining to preserve water quality.

Water Tank Costs

Poly water tanks often cost the least. The poly tanks are classified into the slim line and round poly water tank. The round poly tank costs more than the slim line for the same capacity. The steel option can cost close to double the round poly water tank. 

Factor in transportation charges and plumbing and installation fees when calculating the costs. Some installers charge for a quote. Another cost is the NSW approval for tanks that hold more than 10,000 liters. 

All tanks require a long-term cleaning and maintenance budget. Underground water tanks need more installation costs because the ground must be excavated to place them. 

Another cost to consider is the tank’s purchase. Some suppliers and manufacturers sell the tanks directly to buyers. Large-capacity tanks are often bought through resellers, and this can have an impact on their pricing. That means buying a smaller capacity tank from the manufacturer may be cheaper, though there are other logistics, such as transportation costs.

Although rainwater is free, it collects a lot of debris, which contaminates it. Thus, it would be best if you considered the expenses for its filtering and treatment, disinfection, and fluoridating to make it safe for use.

Some local authorities have rules on the water’s health standards and storage to ensure its safety and to alleviate risks such as mosquito breeding. 

With such costs in mind, it is prudent to balance the tank size with such costs to ensure the expenses are practical about the amount of water harvested and needed.


An affordable and cost-effective water tank size depends on its utility in ensuring a steady and clean water source. A buyer should consider how long the tank should hold water till the next wet season. It is wise to factor in indirect costs, too, when calculating the most convenient and appropriate water tank size for your needs.