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Water Filter Candles

Water Filter Candles

A water filter candle is a type of water purification system that used remove impurities from water. The candle is made of porous materials such as cotton, paper, ceramic. The pores in the material allows water to pass through but traps impurities such as dirt and bacteria. Filter candles can be used to clean most types of water including fresh and dirty water. However the more dissolved impurities in the water the quicker the filters will get clogged up and need to be replaced. They can last for many months with the proper care. They do not require electricity to run as the water is filtered under gravity.

Risks involved with using water filter candles are that if they are not cleaned frequently and replaced when required, the water quality is reduced. Any cracks or damage to the filter could also reduce their effectiveness. This could lead to impurities leaching back into the filtered water and harmful bacterial growth in both the filter and filtered water. There is also the risk to the water quality if the vessel
that the filtered water is stored in is not clean and maintained properly.

The filters are simple to clean. The user should check the manufacturers guidelines for how to clean the filters and how often they should be replaced. As a guide, the filters can be unscrewed from their plastic casing. It is recommended that rubber gloves should be worn and that they are cleaned with clean warm water and a soft brush or damp cloth. It is not recommended to use soap or detergent and it is recommended that they are cleaned and inspected every few weeks or when the water starts to percolate more slowly. Rough guidance suggests that the candles
should be replaced every 6 months depending on usage. As the filters can collect microbes it is recommended that you wash your hands after cleaning or replacing the filter and if you are immunocompromised then it is recommended to get someone else, if possible, to replace the filters for you.

Doulton candles are cylindrical water filter cartridges that can be connected directly to the tap. They contain layers of porous material that water passes through before it emerges from the mount. The outer shell is made of ceramic and has pore sizes less than 100 microns. Within the ceramic, silver is used to inhibit growth of bacteria. The inner core is made of activated carbon which filters out impurities and improves the taste and odour of the water. Various pre-filters can be added to further improve the quality of the water. This might include Ion Exchange Resin to remove heavy
metals such as lead or to help soften the water.

Water Filter Candles – FAQ

What happens if I do not use my filter for a while?

You may notice a change in taste. It is advised to run the water through the filter for about 5 minutes. It is good practice to check the filter for damage before use and also to check the manufactures guidance.

Is the filter effective against bacteria?

The filter should remove bacteria however they can regrow or re-contaminate the water further downstream of the filter so it is important to disinfect downstream of the filter.

Does the filter remove manganese and other metals?

The filters remove metals in particulate form, but not metals in solution.

Does my filter work on water hardness?

A prefilter can be added to help with limescale.

Why does the total dissolved solids and pH increase when using a Ceramic
Water Filter?

A slight increase in total dissolved solids will be due to the presence of the natural mineral Wollastonite (calcium inosilicate mineral (CaSiO3)) in the ceramic. Wollastonite is slightly soluble in water, so may partly dissolve in the water as it passes through the filter.
The slight increase in pH of water passed through the ceramic filters is due to the presence of soluble, minerals in the ceramic. These minerals are Calcium and Magnesium which are both soluble and may partly dissolve in water as it passes through the filter causing a minor pH shift.

Are Candle Filters recyclable?

Depends on the manufacturer. It is best to check with them. Some companies with recycle the plastic parts for you and the ceramic part maybe composted.

Are there any risks that need to be considered when using these filters to treat water?

Water filters only work well if they and the vessel that the water is stored in is well cleaned and maintained. If not properly maintained then there is a risk to water quality. If the filter becomes blocked or damaged then harmful microbes can build up and could cause gastrointestinal issues such as vomiting and diarrhoea.

It is also important to consider how much water you are using before choosing a filter to make sure that you choose one that meets your needs. Choosing the wrong type might mean that more cleaning and maintenance to the filter is required and it might
need replaced more often adding to the overall cost.

Not all filter candles remove all contaminants so it is a good idea to check the manufacturers specification before choosing a filter.
It is also advisable to buy from a reputable supplier as there is a market counterfeit filters. These are often cheap and they may not perform as well as they claim that again could reduce water quality and be harmful to health.