How long can you keep pure-water for?

How long can you keep pure-water for?

Fri 4 Oct 2019

Something that gets asked a lot when to comes to pure-water is how long can it be kept without losing its purity. In short, the answer is forever. However there are a few factors to take into consideration if you are planning on storing pure-water for a while, and want it to be in tip-top condition. We have explained them below.

Firstly, it will depend on what you're storing the pure-water in. No matter how long you intend to keep purified water for, you must always make sure you use a clean container/tank to put it in. Even if the water is 0TDS when it is dispensed, if the container its going into is contaminated then the water purity will be affected within seconds. You must also make sure the container/tank is airtight and nothing can get in whilst it is being stored. It won’t take much dirt to contaminate the whole tank, and if it is left open or uncovered this could quite easily happen and all your pure-water will be unusable.

     

It also depends on where the container/tank is kept. Aim to keep it in cool, dark conditions away from direct sunlight. If the container sits in a warm bright room with sunlight shining on it, there is a chance the molecules in the plastic could break apart and leach into the water, leaving it contaminated. You can reduce the risk of this happening by making sure your storage container/tank is made from HDPE (High Density Polyethylene Resin) as this is a stronger plastic that is harder to break down. Another risk with the water container getting warm is the build-up of Legionella bacteria. As bacteria love warmer conditions this will also contaminate the water, however please bear in mind that if the water becomes contaminated, it does not necessarily mean the TDS will be affected. Therefore if you are using the pure-water for cleaning purposes only, the above contaminations should not lessen the cleaning power of the water, but if you are using the water for other uses such as in an aquarium fish tank, then you should be careful and carry out tests before use.

To summarise the above, keeping pure-water for long periods of time will not affect the purity & TDS levels. However you must make sure you store it in the correct container and environment for the best result. If you have any questions, please give our team a call on 0800 35 76 76 and we will be more than happy to help.