How to Clean a Water Tank

Sand, mud, and bacteria form part of what can grow inside a water tank if it stays dirty. Learn how to easily and safely clean it!
How to Clean a Water Tank

Last update: 12 October, 2021

Water is an indispensable resource for life and for an infinite amount of tasks. For that reason, in the majority of homes or businesses, there are recipients to collect it. These containers can be installed underground, above ground, or on rooves. Perhaps you have often wondered how you would clean a water tank, or maybe this important concept has never crossed your mind.

It’s true that water tanks often get dirty quite easily because they’re the perfect space for microorganisms that can bring health problems. If you want to learn how to clean yours in the easiest, safest, and most effective way, don’t stop reading!

Why is it important to clean a water tank?

This chore is essential to prevent or remove the accumulation of contaminated waste that helps different types of bacteria that are harmful to our health quickly accumulate. If you don’t clean it, for whatever reason, you’ll quickly notice that it will become full of algae and limescale. When this happens, the microbes multiply.

As you can see, the well-being of your family and any other person who uses or consumes the water depends on the cleanliness of these containers. However, regarding how often you should clean them, there isn’t a definite rule, but, as a minimum, we recommend that you disinfect them completely every six months.

How to clean a water tank

Perhaps, to begin with, it may seem like a tedious job, however, once you know how to do it properly with the right materials, it’ll become simple, like any other domestic chore. Follow these steps to get it sorted!

1. Keep the tools and cleaning products on hand

You don’t need a lot of things to clean a water tank. It’s enough with some cloth, a new or sterilized toothbrush, a bucket, and a spade. For a chemical disinfectant, a good option is chlorine or bleach.

But, don’t forget your rubber gloves to protect your hands from the abrasive action of the products. Never use metallic brushes, detergents, soaps, or cleaning powders!

assortment of cleaning products in a bucket
It’s important to use your cleaning products with care and precaution to avoid adverse effects.

2. Take out almost all the water in the tank

Make sure you turn off the faucet that supplies the tank and open the cleaning valve so that the accumulated water can leave. You can use a bucket to make the process quicker and easier.

Don’t get rid of all the water. Leave about 5 inches, but be careful you don’t shake it to avoid spreading the dirt.

3. Clean all the areas of the tank

Scrub the walls, the back, and the lid vigorously, starting with just water and no other additional product. Pay special attention to the most hidden corners, the edges, and the water inlets and outlets; that’s where the most dirt usually accumulates.

Remove the residue with a spade and chuck it into the bucket. To remove the contaminated water, open the drain pipe and never use the distribution pipe.

4. Fill the tank to the middle with water and add chlorine

At this point, you’re about halfway through. The proportions to use are very simple: if the tank is a thousand liters, add one liter of concentrated chlorine; if it’s 500 liters, only add half a liter.

Be very careful when dealing with chlorine, especially avoid contact with your hands and eyes. Allow it to breathe for at least an hour so that we get it to do what we want.

5. Rinse until all of the chemicals are out

Empty the water tank again and rinse it as many times as necessary to ensure all of the bleach is out. Then, take a good look at how your tank is looking.

If you notice yellow, brown, or green marks, give it a scrub and apply more chlorine. These stains are evidence that the bacteria are still there. You’ve got to get rid of them completely!

Next, with the help of a damp cloth, remove the rest of the chlorine that could still be there. After that, wipe it over with another dry cloth. The rag must be made of cotton or a similar fabric so that it doesn’t shed any hair.

6. Fill the water tank

Once you’ve finished your cleaning process, open the valve to allow the tank to fill up as normal. Check that the water is coming out properly.

At the same time, open some faucets in your house for a few minutes. This way you’ll avoid any accumulation of air. When the water reaches its normal level, screw the lid on very tight to prevent anything from falling into the tank.

7. Don’t forget to clean it again!

A piece of advice: you shouldn’t forget to scribble in your diary, your telephone book, or anywhere you’ll remember the date you last cleaned the water tank, to know when you need to do it again.

As we said at the beginning of this article, you should do it twice a year. However, you should do it more frequently if the water that you get contains more salts and has a tendency to produce more limescale.

open faucet in a house
It’s important to open a few faucets in the house when you go to refill the tank to prevent the accumulation of air in the pipes.

How to dispose of the accumulated waste

When cleaning the water tank, you’ll inevitably find liquid and solid waste that includes chlorine, limescale, dust, sand, and even the bristles of the brush you used to clean it.

You can scoop this up with the help of a disinfected spade and a plastic bucket. After rinsing, the tank’s drainage system should remove the water.

Cleaning  your water tank helps maintain your health

When it comes to getting a tank, make sure that it’s strong and easy to clean. The most popular tanks are made of polythene because they’re lighter and easier to maintain.

Always make sure that they have antibacterial protection. However, it’s more important that they have a hermetic lid.

Install the tank in such a way that you’ll be able to access it to disinfect it, without it being a danger. It’s a good idea to schedule your cleaning a few days in advance; this allows you to take advantage of the water to clean your clothes, wash the toilet, or water the garden. The idea is to not waste this resource.

Another key part when it comes to cleaning your water tank is that all the members of the family know you’re doing it. This way, you can confirm that no one will consume the water whilst you’re disinfecting it, because that would be even worse than the previous contamination.

For its part, the Pan American Health Organization (PAHO) highlights the importance of keeping water tanks covered. This way there’s no possibility of polluting substances, as well as dust, dirt, animal feces, or anything else that causes disease falling in.

Similarly, in addition to constant cleaning, it’s a good idea to install filtration and purification systems. Your water will be cleaner and safer than ever!

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