That is an easy fix..... though no polar bear (but a cub) is WHITE. Algae in the fur is not new or a a shocker. It happens when they are kept in areas other than their natural temp range. Wonder what they keep their water temps at. They need to do something about WQ (like addition of ozone to control algae levels).
I would start with the idea of less water changes being 'conservation' while watching it have a negative impact on the visual appearance of the animals. More changes are needed, just address the algae issue.