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Water Tank Aeration System for Rainwater Tanks

Water Tank Aeration System for Rainwater Tanks

AqueousAir™ is a water aeration system that will oxygenate and circulate the water in your rainwater tanks at a sub-surface level, helping improve your water quality whilst ensuring you get the most out of your stored water system.

The only time your water is naturally oxygenated is when new water is introduced into your water tanks. Whether that’s from rainfall collection, water delivery or being pumped from dams, rivers or bore systems.

Over time, as water sits idle in your tanks, oxygen in the water dissipates. With the addition of sediment on the bottom of the tank, this creates what is referred to as an Anaerobic level.

Anaerobic conditions, where organic matter builds up at the bottom of the tank will cause bacteria to grow. Resulting in smelly or poor tasting water.

Not only is this the ideal breeding ground for bacteria, but as your water sits idle, oxygen dissipates. In simple terms, your water becomes dull or dead.

Dissolved Oxygen (DO) is a measure of how much oxygen is dissolved in water. DO is present in all rainwater due to contact with the atmosphere. It is essential for quality of water. Without DO, water becomes stagnant.

Most water tank storage systems extract water from the bottom of the tank. After periods of no rain and hot weather, with water sitting stagnant, the Anaerobic level increases and the depth of quality water decreases. DO levels are decreasing, and this is when water can start to smell.

To maintain the best quality drinking water in your rainwater tanks, your maintenance program should include:

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Clear Catchment

1. Clean Catchment Area

Ensure water catchment and storage is regularly inspected. Eg. Check that openings are closed. Roofs, gutters, and other  catchment areas should be clean and free from debris such as leaves, flowers, dirt, and any other contaminants.

Water Tank Cleaning

2. Vacuum/Filter Water Tank

Cleaning removing organic matter out of the tank as necessary (at least every 2 to 3 years).


3. Sanitise Water System

Sanitising your water/tank and the pipework through to the taps.

Water filter

4. House Filtration/Ultraviolet Unit

Filtering and then disinfecting with an Ultraviolet system before the water enters the house.


5. Oxygenating Your Water

Oxygenating the water periodically between periods when there is no rain or water is not being added into the tank.

The AqueousAir™ water aeration system allows you to oxygenate and circulate clean air into your water tank. The unit is raised off the tank floor and will agitate water around the tank. Drawing air down to the bottom of the tank, the full depth of water will be properly revitalised with dissolved oxygen, to invigorate and rejuvenate your drinking water.


Z Prevents stagnation of your drinking water between long periods of rain
Prevents anaerobic conditions in your tank, where the lower levels of water have low or non-existent oxygen levels
Increases the depth of usable and vitalised water
Reduces bad bacteria population, helping to remove bad smells and tastes
Using sub-surface aeration to introduce oxygen to the lower levels of your water tank

How does it work?

AqueousAir™ is a static, sub-surface water aeration system that operates by delivering the appropriate volume of air directly into water flow using venturi technology.

Water and air are delivered directly into the system via a submersible pump, injecting water whilst drawing air simultaneously. This mixes the air and water as a pressurised mixture into the water tank, circulating and reinvigorating your water.

The AqueousAir™ water aeration system will effectively and efficiently aerate water in tanks from 5,000 Litres to 50,000 Litres*. Air is sucked into the tanks at a rate of 70 litres per minute. Therefore, a 25,000 Litre tank will take 6 hours to be completely circulated. For regular aeration, operating your AqueousAir™ water aeration system is adequate for approximately 1-hour per day for most water tank situations.

During periods between rain or manually topping up your water tanks, the AqueousAir™ water aeration system can be used for as little as half an hour a day. Oxygen will be agitated into the water, ensuring you have little to no Anaerobic levels in the bottom of your tank. This will provide greater depth of usable water.

The AqueousAir™ water aeration system is best used in water tanks that have had the organic debris and sediment layers removed from the tank(s). If there is organic matter and sediment in the tank, this will also be circulated around and could end up discolouring your water. If a Whole of House filtration system is installed, this will filter the water before it enters the house, however it may also require more regular filter cartridge changes.

The AqueousAir™ system utilises sub-surface aeration technology to introduce air into the water. Compared with Surface Aeration methods, sub-surface aeration is far more efficient. A higher volume of water can be circulated at a faster rate to achieve the required levels of DO. This will save energy and with regularly timed operations, ensure you have optimal Pristine drinking water.

*We are also able to offer options/solutions for larger tanks

**Water volume and quality depending.

AqueousAir FAQs

Why do I need to oxygenate my water?

Healthy water needs adequate dissolved oxygen. Rainwater naturally oxygenates as it falls through the atmosphere and flows into your water tanks. But as water sits idly in the tank, oxygen levels are depleted. Your water is only oxygenated when new water is added.

Without an aeration system, your drinking water will stagnate. Just like a fish tank, you need to introduce oxygen to ensure your water remains vibrant, healthy, and alive!

Why use AqueousAir?

AqueousAir has been specifically developed to introduce oxygen into rainwater tanks used for everyday drinking purposes. Unlike systems that are designed for ponds or fish tanks, AqueousAir will efficiently circulate water in tanks up to 50,000 litres, while the AqueousAir Plus can operate in tanks up to 250,000 litres.

AqueousAir utilises sub-surface aeration technology to ensure a higher volume of water is circulated at a faster rate, ensuring all the water in your tanks reaches the optimal oxygenation levels.

Will AqueousAir stir up sediment in my water tank?

If your rainwater tank has not been cleaned and has a build-up of sediment, then you may experience dirty water directly after AqueousAir has been in operation.

We recommend that your AqueousAir is installed with a timing mechanism to operate in the early hours of the morning so that any sediment has sufficient time to settle before your household requires water.

AqueousAir is best operated when your rainwater tank has been cleaned and sanitised, and if you have a water filtration system to remove sediment before your water is used in the house.

How long do I need to run AqueousAir to optimally oxygenate my water?

For most rainwater tanks, AqueousAir only needs to be operated for 1-hour per day. During periods of rain, you can turn your AqueousAir off. For optimal water quality, running AqueousAir daily in the early hours of the morning will ensure you have vibrant healthy

Like to find out more about joining the PWS team?

Pristine Water Systems currently have over 17 Franchisees operating in Queensland, New South Wales, Western Australia and expanding. We have opportunities across the country in some very exciting regions. If you are interested in working together, send us an enquiry and we will get back to you as soon as we can!