Pink water looks alarming but it’s not harmful.
The colour is due to purple sulphur bacteria which grow when there’s an abundance of plant debris in the bottom of the pond, producing a lot of hydrogen sulphide gas (the smell of rotten eggs). Purple bacteria use hydrogen sulphide instead of water to power their photosynthesis.
Pink pond near Derby, 5th November 2008 (thanks to Nick Sanderson at EMEC Ecology)
Pink ponds may be the result of a perfectly natural build up of plant debris or the result of pollution by rotting organic matter or sewage.
So being pink doesn’t automatically mean your pond is polluted – but it does mean it has a lot of organic matter.
Thanks to Scott for the photo of water from his pond, and Nick and Chris for the pond photo.
Tags: Pink ponds, Purple bacteria
