The Best Way To Keep Your Rainwater Tank (And The Water It Holds) Clean

No matter whether you use it for drinking, household use or irrigation, maintaining a high standard of water quality in your rainwater tank is crucial. There are a surprisingly large amounts of factors that can affect the storage and output quality of your tank so it’s a good idea to look into how you can best ensure clean water.

It may seem obvious that the best way to maintain the cleanliness of your tank water is to keep your tank clean but there’s a bit more to it than first meets the eye. Plus, many people reported that they didn’t know that in addition to the standard cleaning and maintenance requirements outlined by the manufacturer, it is also important to clean your rainwater tank after events such as dry spells and dirty rain.

As with most cleaning regimes, it’s best to start at the top and work your way down.

Gutters and pipes should be regularly checked to ensure that they are free of debris and blockages. Climbing plants love invading pipes and those in particularly wet climates may even encounter aquatic weeds growing in these areas.

From here, you should move down and clean any external coverings and the intake of your water tank.

Once outside areas that are likely to impact internal conditions have been cleaned, it’s time to look inward.

Like all waterbodies, rainwater tanks are prone to collecting sludge on their bottom when left to their own devices. If you have an open top tank (generally installed for irrigation or livestock watering purposes) you’ll be able to remove this organic wasteland with an aquatic vacuum but if you have an enclosed tank it is best to enlist a professional to clean the interior as water tanks can be quite dangerous (and in many states it’s actually illegal to enter and work within an enclosed space without appropriate licences).

Once you’ve completed these steps, it’s time to clean and flush the plumbing between your tank and your water’s destination and viola, you’ve got a nice, clean water tank which will give you far higher quality water than it did before.

If you want to maintain this high water quality standard for a prolonged period of time, it is a good idea to aerate your rainwater tank.

It may seem strange to add oxygen to water that you don’t want aquatic plants or creatures living in but aerating water tanks actually carries a number of benefits including:

  • Preventing stagnation – this leads to tastier, cleaner water.
  • Dissuading insects from moving into your tank – yes this is a thing and although it probably won’t kill you, it certainly isn’t ideal.
  • Reducing algal blooms – yup, your tank can have those too and no it isn’t pretty, especially since algae can be highly toxic.
  • Preventing anaerobic conditions – water which has low or non-existent levels of dissolved oxygen will smell and taste gross and can be dangerous to your health, by aerating your rainwater tank you prevent this from happening.
  • Reduce bad bacteria populations – Aerobic bacteria (good, oxygen loving bacteria) can outcompete nasty bacteria when provided with ideal conditions.


Aeration can also help clean water that has been contaminated and must be discarded, therefore reducing the environmental impact of releasing said water. This is particularly beneficial in areas that have been affected by events such as dust storms or the recent bushfire tragedies.

If you have any questions about using an aquatic vacuum or aeration for water tanks, please get in touch with our friendly expert team on 1300 005 670 or via the contact page of our website.