A spokesperson for SEPA said: “SEPA received a report from a member of the public regarding a red algal bloom in Loch Long. This is suspected to be a natural algal phenomenon more commonly known as a Red Tide. The algae may colour water red, rusty-brown, green or not visibly change it at all. (Image: Vladimir Wang on Unsplash)Read More:A "red tide" bloom develops when the right species of algae, nutrients and water conditions coincide. Human nutrient pollution can worsen or extend some blooms, but it is usually inaccurate to attribute every red tide to a single cause.