Algae is a pretty important organism. The first plants on earth probably evolved from algae. It's used in food, fertilizer and sewage treatment. Oh, and algae can also eat raw industrial smokestack emissions for breakfast.
Talking to your relatives or friends about climate change can be an uncomfortable situation. Everybody has the right to prioritize issues in their own lives, and nobody should feel talked down to by someone who is concerned about the climate apathy many Canadians feel.