Translations:Water - Biosand Filter/76/en

The filter is very simple to use, just like caring for a houseplant. The most important part of maintenance is to ensure that the biological layer stays healthy by feeding it one to four times a day with contaminated water. Once fed, the biological layer must digest and recover, so there must be at least one hour between each use. Just like a house plant, the biological layer cannot survive if there is too much or too little water. While the filter is not being used, a 5cm layer of water covers the top of the sand. This layer must be maintained or the living microorganisms may die. If cloudy or visibly dirty water is poured through the filter, the sand will accumulate dirt which will slow the flow of water. To correct this, a non invasive method that does not disturb the biological layer called stir and dump is used to clean the top of the sand and improve the flow.