Steel water tanks pros:

• can be made to any size due to the manufacturing process
• can be made in larger sizes as they can be made on site
• can have additional poly lining to protect against leaks
• they have the traditional look and can be more glossy to repel heat

Steel water tank cons:

• are not made in one piece
• can be expensive
• need a concrete pad
• need to be lined in poly to give added protection
• are more delicate if need to be moved
• can be given dints which can cause week spots

Poly water tank pros:

• poly water tanks are more durable
• poly is longer lasting
• poly tanks are thicker and will not ding
• water tanks made from poly can be relocated easily by rolling or even sliding along the ground
• poly tanks are now made with food grade poly that is uv stabilised
• they are relitivly inexpensive
• need less base preparation

Poly water tank cons:

• are limited to about 50,000 litres due to them being made in a factory and trucked out
• sizes are limited to what moulds the manufacturer has available

Rotational moulding process is also used in the manufacturing of Polyethylene tanks used for water storage. This method of manufacturing polyethylene tanks brings a lot of design advantages. Using this process results such as strong outside walls that are of uniform thickness and stress free corners.

Making water tanks using rotational moulding process involves four stages or steps.

As a first step, the polymer has to be loaded into the mould. The mould should be a closable unit, which is in the shape of the product that is being manufactured. Measured amount of polymer resin has to be loaded into the mould and the polymer resin can be either in the form of powder or liquid. The polymer used will vary depending on the product that is being manufactured and in the case of Polyethylene tanks, the most widely used polymer is plastisols and polyethylene. Required  colouring agent is added along with the polymer. When the mould is loaded with the required amount of resin or polymer, it is sealed and moved into the oven. Before moving the mould into the oven, the oven should be prepared by preheating it to 260°C - 350°C based on the polymer used.

In the second stage involves heating and the fusion of resins. This is one of the most crucial stages of the rotational moulding process. The oven used for rotational moulding process has special equipment that is capable of rotating the mould in bi-axial directions. The mould is continuously rotated at a low speed and the ideal speed for rotations is 20 rotations per minute. The duration for which the mould is in the oven is very critical. If the mould is not in the oven for enough time, then the polymer will not melt fully to stick to the walls of the mould. It will also form air bubbles in the product affecting the strength of the product. The purpose of this second stage is to melt the polymer and make it fuse to the walls of the mould. The mould is rotated in biaxial directions to ensure uniform settling of the polymer to the walls of the mould. The rotation should not be should not be centrifugal motion because centrifugal rotation will make all the polymer settle in one end of the mould.

The mould cannot be in the oven for too long either and if it stays in the oven for too long then it will affect the quality of the product and the impact strength of the product will be undermined and the mechanical properties of the product will be highly compromised. This becomes all the more important in the manufacturing of water tanks used for storage purposes. Only when the temperature and the duration inside the oven are perfect we will be able to get good quality Polyethylene tanks.

The next step involves cooling of the mould. The cooling stage is as important as the fusion stage. This phase takes longer than the heating and fusion phase. The strength of the product will be established during the cooling process. Cooling has to take place in a gradual and natural fashion using fan. As the mould cools, the fused polymer inside the mould solidifies. The mould cannot be handled when it is still hot. Moreover, it the mould shall not be removed before it cools fully because the product solidifies and gains its strength only during this phase and if the mould is opened before proper cooling, then the shape of the product too can be affected. Once the mould cools completely, it will shrink and the opening of the mould will be lot easier. Rapid cooling of the mould is not advisable. Rapid cooling can result in products that have poor mechanical strength and warped parts.

The final phase in the manufacturing of polyethylene tanks using rotational moulding process is the unloading of the mould or demoulding. The mould is removed from the finished product once it is cooled down. The finished product is sent for quality checks while the empty mould is filled with the polymer for the next tank.

Today the rotational moulding process of polyethylene tanks has been perfected using the latest technology. The quality of the product is no more a question of trial and error. The success of the process does not depend on the judgement and experience of the operator. The modern process allows the air temperature to be monitored throughout the process ensuring perfection and uniform quality of each product subjected to the rotational moulding process.

As rotational moulding has many advantages in the manufacturing of polyethylene tanks, Many Australian water tank companies make use of rotational moulding in the manufacturing of all its tanks. The over all cost of rotational moulding is much cheaper when compared to the other moulding processes while the quality of the water tanks obtained through rotational moulding process is much superior to the other moulding processes. These advantages are passed on to the customers directly both in terms of the cost of the product and the quality of the product.

Rotational moulding process allows uniform thickness of the walls of the water tanks. This is one of the most important qualities of a water tank that is used for storage purposes. If the wall strength should vary from one spot to the other, the water contained in the tank can exert pressure on the weak spot and damage the take over a period of time.

Increasing water scarcity in Australia is a matter of concern to the Australians. A lot of money is spent on buying processed water and the cost of water is rising drastically. All the measures taken by the government to conserve water are not enough to combat the situation. One of the ways of handling the problem is to erect personal water tanks to store the rainwater.

People are becoming increasingly conscious about this alarming problem and are on the lookout for sustainable solutions that will not burn a hole in their pockets. Australian droughts are world famous and unless enough measures are taken, the future generations will be spending 10 times than what we are spending on our water bills. Installing water tanks is the most cost effective ways of handling our water problem. These water tanks can be used as standalone tanks or as backup tanks for our existing water tanks. This will reduce our water bills to a considerable extent.

Those who have gardens can make use of the rainwater saved to keep their gardens watered and green. We will also never run short of water for our personal use. By investing in water tanks we will save ourselves from a lot of water related problems and also we will save a lot of money on the long run. Compared to the amount of problems it solves and the amount of sustainable savings water tanks bring, it is certainly a wise investment.

When more and more people install water tanks we can save a lot of water as a nation. This will bring down cost of the water bills. This will also give enough time to replenish the natural sources. We can save up to 40% of water by installing water tanks and using rainwater collected in water tanks. This will not only save so much of water, this also will save us 40% of the water bills. Imagine the amount of money we could save annually by installing a water tank.

When we decide to install a water tank, we must ensure that we buy our water tanks from a reliable vendor. Water tanks in general will be exposed to the harsh weather conditions, sunlight, rain and snow. So the water tanks that we choose must be suitable to meet all these harsh weather conditions. Unless we get a good quality water tank it will not be able to withstand the harsh weather conditions of Australia. If we do not pay attention to the quality of the water tank that we install, then we will be spending a lot of money on replacing the water tank. Therefore it is always wise to spend some time in finding the right vendor to buy our water tanks so that they will last a lifetime.

To meet the varied needs of the rural consumers today we get water tanks in a variety of shapes, sizes and colors to suit any environment and need. The cost of water tanks vary depending on our needs. While selecting our water tanks we must therefore look for quality products that fit well within our budget. We must also make sure that the material used will withstand the harsh weather conditions. The tanks should not get corroded or rusted. We should be able to get water tanks that meet our size requirements.

water tank companies ship their water tanks all over Australia and they are tested in all possible Australian weather conditions. They are one of the most durable water tanks. The cost of these water tanks are highly competitive. It is not enough to find a water tank that costs less but it should also have long life.

Before finding the right sized water tank for your area, you must find out the average rainfall in your area so that you can order the right sized water tanks for your requirements. Select your water tank today and place your order. This will give you more control over your water needs. Month after month you can save on your water bills too. You can use the water saved for watering plants, for your animals as well as for your personal usage after proper purification.

From a rural perspective water tanks have been an essential part of life for most of australian farming history they have provided a back up means of water storage in the dryer times and have allowed pottable water to be collected from rain when flowing water was not at its best. this aspect has remained relitivly constant with water tanks becoming more and more essentail as well as a more reliable means of containing water compared to dams. Reasons being that the technology in the designs and manufacture of the tanks has improved and so has the primary producers confidence in their reliablility.

For the semi rural parts of australia there has been some interesting regulations in the past for the use of water tanks at one point or another mains water becomes available to the fringes of rural areas in this case a farm outside the town of a rural town was eligble for mains water which is fair enough. However, after the mains were connected a letter was recieved stating that water tanks were not to be used if mains water is hooked up so naturally the primary producer disconnected the mains at a large cost. This was also the same rule in the city at the time and this is not to long ago either when it was acually not permited to have a water tank in a suburban area.  A rather interesting timeline of events in legislation I think considering now that the state and federal goverments rebate up to two thousand dollars for installing a water tank in an existing suburban home and now require in basix that all new houses have at least 10,000 litres installed. 

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