Water Treatment

Cleaning and disinfecting a cold water storage tank

Keeping your water storage tank clean is absolutely necessary, to maintain your control over legionella proliferation. Listed below, are some of the reasons that your tank should be cleaned regularly.


  • Silt and scale, mostly from hard water, can build up quickly, and if left in a tank, provide a great 'food' for bacteria.
  • As well as silt and scale, organic matter can enter, and seriously taint, water in the tank. This is the reason that visual assessments, of the tanks themselves, are important. 'Organic matter' can be anything from small pieces of debris, from outside (such as leaves), to animals (most commonly in the UK, rodents and birds). The larger types of debris are excellent food sources for legionella and all other types of bacteria. Some organic matter even introduces bacterial contaminants that can cause various different illnesses.
  • Under-using you water can be a big problem. Again, this can cause stagnation of the water. In these cases, we ask our clients to consider reducing the size of the tank, isolation of a tank or to move their ball float to an appropriate level.
  • Any blockages can result in poor flow and stagnation, or provide a nice, large breeding ground for bacteria that can, slowly but surely, enter the whole system.


There are ways of making sure that your system is clean, after the tank areas have been disinfected, through the use of quality cleansing chemicals, that are slowly pulled through the system, and flushed out, prior to commissioning the water for use.

If you are a building maintenance provider or a building manager/duty holder, it can be difficult to manage various things at once, and sometimes tank cleaning and disinfection can easily be overlooked.

We know, as contractors, that many people, before employing us, have neglected their tanks (and we certainly have some dreadful horror stories because of this). if you are one of these people, you are not alone, but you should have your tank checked and cleaned, especially if it holds water for drinking use, as dirty or poorly maintained tanks are a main contributor to contaminants that can, 1. make people very ill, and 2. make legionella very happy.

To help you gain some insight, we are happy to come and check your tanks and explain the correct course of action. To arrange a meeting, of this type, please call 0870 729 0199 to chat a friendly consultant.

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