Various impurities accumulate in every fountain over time: the lime from the water settles on the water nozzles and other materials, algae turn the fountain and water green and, moreover, flowers and pollen, leaves and other dirt constantly fall into the water. Therefore, a fountain and the water in it must be cleaned regularly.
Cleaning a fountain with chlorine is not a good idea
Top tips for cleaning fountains
Probably the easiest way is to simply spike the water with chlorine or other biocides that will keep it clear and free of algae. However, this method is not recommended for outdoor fountains, since birds and insects like to use such a water source as a drinker - and subsequently suffer from poisoning. Instead only helps
- to keep the water constantly flowing and to connect it with a planted garden pond, stream, etc
- Moving water pollutes significantly less than "stationary"
- Aquatic plants in particular greatly reduce algae growth
- change the water regularly
- allowing the fountain to dry out and cleaning it thoroughly before refilling it
- to keep the water values in an optimal range
tips
You don't need expensive supplies to clean a dry well: Potato water (i.e. the cooking water from potatoes) works wonderfully for this purpose.