Water Tower

Keep Mosquitoes Away from Water Storage Tanks


Mosquitoes are a nasty pest that have the potential for carrying disease. Read this guide for tips on keeping mosquitoes out of your water storage tanks.

With mosquitos at large in southern Australia, some of them carrying the Ross River, Barmah Forest viruses and even some life-threatening diseases, it’s wise to take precautions to keep your water storage tanks mozzie free.

Mosquitos love standing water, so your water storage tanks are a natural choice for them. That being said, they can also lay their eggs in as little as 3cm of standing water, meaning it’s not just the tank itself that needs attention.

Follow our guide, and you’ll stand a much better chance of keeping them at bay, and preventing them from moving in.

Prevention Better Than Cure

It’s much better to take steps to prevent mosquitos finding places to spawn when you’re installing or renovating your water storage tanks. You’ll find it much harder to remove them once they’re installed.

If you’re thinking about getting yourself a rainwater tank, but aren’t sure which type is right for you, check out our guide by clicking here.

Once you have your tank, the key is blocking up potential points of entry and ensuring that leaks do not occur, which could provide another area for them to colonize. Read on for our suggestions.

Protecting Your Water Storage Tanks

When installing your rainwater tanks, it’s important to think about each point that mosquitos could potentially access it, and take measures to seal them to prevent access.

First Line of Defence

Apart from when they are actually being used, all access points should be sealed. This means having close fitting lids over them.

Inlets and overflows also need to be protected. Some states, including Queensland and Northern Territory, even legislate on this point, it’s so crucial.

The screens that you put on these points of water entry or exit need to be close fitting and removable.

For example, Queensland dictates that they must be made of brass, copper, aluminum or stainless steel gauze. The aperture should be no coarser than 1mm.

Although other states don’t currently legislate on this, this provides a good guide for the type of measures you should be putting in place on your water storage tanks.

Ongoing Maintenance

With a new tank system, you do not have to worry about corrosion or gaps occurring because of wear and tear. However, over time, this needs to be considered.

Regularly inspect the whole tank for any signs of corrosion or gaps developing. Mosquitos will exploit these to enter and lay eggs in the water.

Also, check the join where the lid meets the body of the tank. Over time, this could warp and develop a gap for mosquitos to gain entry.

Around the Water Tank

It’s very easy when collecting rainwater run-off to develop a leak in the system. This can then develop into small puddles or pools of water that are heaven for mosquitos looking to breed.

When you install your system, always run water through it to simulate what it will do when in use. Identify problem areas and put measures in place to prevent water from leaking on its way to the water storage tanks.

Watch the area around the tap too. It’s tempting to put a small container under a slightly leaky tap, but this will only exacerbate the problem. Make sure all leaks, however small, are dealt with straight away.

Gutters are another area that needs to be kept clear of any stagnant water. Obstructions from leaves and other debris can quickly cause a water backlog. make sure that they are regularly cleaned to prevent this happening.

If your water storage tanks are fitted with a first flush device, they also need to be regularly cleaned and emptied. As they work by building up a water barrier to debris and pollutants, this could itself become a breeding ground for mozzies.

Regular inspections and maintenance are also vital as these systems can wear and leaks can develop over time.

Last Resort – Removing Larvae From Tanks

You’ve taken all the precautions, been diligent about maintenance and yet the blighters have still taken up residence. Now it’s time to take drastic action to get rid of them.

There’s no treatment option that guarantees removal of the mosquito larvae, also known as wrigglers. You also need to consider what you use the water for. If you are planning to drink it, check first that your treatment option will result in safe water.

Possible treatments include:

  • Adding a teaspoon of medicinal paraffin or domestic kerosene (please note, commercial or industrial kerosene, such as that used for powering farm vehicles must NOT be used)
  • Also, note that kerosene cannot be used in Aquaplate tanks
  • A Licenced Pest Management Technician can come and administer briquettes containing S-methoprene 18g/kg. One briquette will protect 5000 liters of rainwater against mosquitos for 6 months and is safe for drinking water

The key to tackling wrigglers maturing is to prevent their access to oxygen, without which they cannot survive. They rely on the surface tension of the water holding them up so they can breathe. Paraffin and kerosene break this.

Creating a ‘skin’ of oil on the top surface of the tank could also be effective. If you’re concerned about using kerosene, some users have noted that olive oil can be an effective alternative.

The Main Point: Keeping Water Storage Tanks Mozzie Free

Our advice can be boiled down to these four key points –

  • Take steps before installation to make sure that you are not providing any environments in which they can thrive
  • Seal off all access points and use an appropriate standard of mesh over outlets and inlets
  • Maintain it well to ensure there are no leaks/puddles that can provide a breeding ground for them
  • If you’ve already got them, do your research to make sure that the method you use to get rid of them won’t ruin the quality of your water.

At Rainwatertanksdirect.com, we know everything there is to know about rainwater storage. We have a wide range of water storage tanks, pumps and more, as well as handy guides to help you get exactly the right tank for your home.

Click here to check out how to order today.