Wild salmon get their orange-to-red colour from carotenoids, which come from the crustaceans (shrimp) or small fish they consume. While there are over 20 different types of carotenoids, the main one found in fish is called "astaxanthin."
Farmed Atlantic Salmon do not access astaxanthin in their diet. To produce a healthy fish, astaxanthin is added to their carefully formulated diet. It's identical to the naturally-occurring compound that gives the fish the healthy colour that you want.
The U.S. Food and Drug Administration and the Canadian Food Inspection Agency both approve of the addition of astaxanthin. So you and your family can rest assured that Heritage Salmon is wholesome and completely safe.