STAINLESS STEEL TANK QUESTIONS

This is the question we get asked most often, and there are several answers :

  1. A Stainless Steel Rainwater Tank has a service life will in excess of 40 years and are designed to withstand the harshest of Australian conditions.
  2. The reputation of Stainless Steel is a strong, durable and hygienic material is unsurpassed – in fact it is mandatory for food and pharmaceutical processing plants, hospitals and other sterile areas. You will have peace of mind when it comes to the quality of your water.
  3. Stainless Steel is fully recyclable
  4. They look fantastic
  5. With an extended service life and reduced maintenance costs, they in fact COST LESS than other comparative tanks over the working life of the tank.

The traditional construction of ordinary, corrugated stainless steel rainwater tanks in Australia involves drilling or punching numerous holes to fix the corrugated sheets together with rivets or screws. Unfortunately, this creates the weakest link in the tank. Each one of these rivets or screws requires complete sealing otherwise it has the potential to be a source of corrosion and leakage.

To overcome this problem Stainless Steel Water Tanks pioneered a unique method of spot welding the stainless steel corrugated sheets and now offers a premium product at a competitive price. Stainless Steel Water Tanks manufactures an extensive range (see Tank Sizes) of reliable, durable, safe and hygienic stainless steel rainwater tanks, with none of the disadvantages of other rainwater manufacturing styles.

Only 1 or 2 items in the tank are not stainless steel. One is the tank overflow which is a moulded PVC fitting. The tanks are sealed (like all steel rain water tanks) with potable water approved silicon.

Provided your tank is clean, mosquito proof and the water is not exposed to light, then the water will last many years even without jeopardizing the drinking quality. This is a qualified statement, assuming your tank is made from stainless steel.

No, stainless steel is not affected by concrete, unlike other steel tanks.

Our recommendation is always to use a concrete base, for the reason that stainless steel on a concrete base will last as long as your house if not longer. We estimate that approximately half of our tanks are placed on crusher dust or sand. This is acceptable, but care has to be taken that the crusher dust cannot be undermined by water or vermin.

It is always a good practice to pipe the overflow away from the tank. Pavers can also be used as a tank base, and provide a good economical base for water tanks. Note that a crusher dust base is not suitable for our super slim and standard slim series of tanks.

The tanks are not designed to be fitted in-ground, and we have no engineering data to state that in-ground mounting is permissible.

The only tank that is truly fire proof is a concrete tank. Although a bush fire cannot harm the stainless steel besides making it black, prolonged exposure to extreme temperatures will eventually destroy the seal depending on how much water is in the tank. The seal is replaceable.

Other tanks do not perform well under extreme temperature. Plastic tanks are known to catch fire themselves in such an emergency. Aquaplate tanks are most sensitive to temperature over 70 degrees. The plastic coating inside the tank will separate and render the tank useless. Zincalume will perform slightly better than aquaplate, up to about 200 degrees when the zincalume coating will melt.

Heavy hail will dent the roof of the tank, comparable to a hail’s damage to a car. The tank currogation will withstand hail with very minor damage. The usual house and contents insurance should cover such damage. Our experience shows that insurance companies would generally pay for a new tank.

Our recommendation is to always install the largest water tank possible within the restraints of your budget, locality and council by-laws. The Australian family of 4 uses approximately 330,000 litres of water per year. Half of this water is used in the garden, flushing the toilet, cleaning the car etc.

With the installation of 2 – 22,000 litre tanks, such a family can be close to be independent from the reticulated town water supply provided that the roof area is at least 200sq meters and most importantly, the gutters are kept clean to avoid any water wastage.

It has to be realised that even minor local showers which are irrelevant to dam levels and town water supply will quickly add 4 weeks of water to your tanks.

A final consideration should be that a larger tank is more cost-effective. Example, a 1,000 litre tank may retail for $800.00 which translates to 80 cents of water/litre stored.

The other extreme is the 40,000L tank retailing for $4,398.00 using the same formula. Cost per liter of water stored is 11 cents.

GENERAL TANK / WATER STORAGE QUESTIONS

Strictly speaking, NO. There is hard scientific evidence that chloride used in town water reacts with the organic compounds (e.g. leaf residue) in your tank to form trihalomethanes (TMHs). THM is a known carcinogen (causes cancer)

Some authorities make recommendations to chlorinate tank water. We have some reservations to this for the following reasons. Firstly, accurate calculations and measurements have to be carried out to ensure the correct amount of chlorine is added to the tank. From my point of view, due to the toxicity of chlorine and the danger in handling it, plus the potential of overdosing, this is no task for the handyman. Secondly, there are much better and safer products available (Aqua Safe or UV sterilisation) which are more suitable and safe to handle.

Opinions are divided but facts speak for themselves. Rainwater has been the only source of water for many decades for our rural and semi-rural neighbours, without any noticeable or recorded effects on their health.

Rainwater should not be collected close to industrial areas (5 km radius) from timber, asbestos or tarred roofs, nor next to crop fields where areal spray is conducted.

Every Council has their own rules and regulations, so please check with your local authority. One hint of advice, numerous customers discovered that to be entitled for the rebate, a plumber has to install and connect the tank to the house.

This must be the most frequently asked question, and unfortunately there is no simple answer or solution. Firstly, it must be emphasised that this problem commenced with the introduction of rain water tanks, and is by no means a new problem.

The consumption of rain water tainted with “wrigglers” presents no health hazard, but can be easily prevented with the installation of a 20 micron filter after the pressure pump.

Ensuring that the tank remains free of mosquitoes, wrigglers and larvae is proving to be more difficult. The assumption that the mozzies somehow get through the screen is wrong, “around it” would be the more appropriate term. Most inlet strainers do not make a perfect seal on the tank. This is true not only on steel water tanks, but also on plastic tanks particularly when the sunlight starts to buckle the plastic.

A 2-3mm gap between the strainer and the tank seem insignificant, but is plenty big enough to let female mozzies enter the tank and lay eggs. We developed a screwed inlet strainer which seals perfectly and allows no gap between the tank and the strainer. Unfortunately this strainers are custom made and therefore rather expensive. The second way for mosquitoes to enter the tank is much more difficult to seal.

Roof guttering will always retain small paddles of water after a rain event. This is the perfect place for female mozzies to lay their eggs, which of course are washed into the tank with the next rain. The 0.98mm aperture of the inlet strainer is far to coarse to catch microscopic eggs, which pass without difficulties into the tank to hatch.

 

 

Designer Tanks:115 Gibson Road Nanneella Vic 3561• P: 0354 84 6298 • E: info@designertanks.com.au