Spirulina is a blue-green algae chlorella is a green algae.Spirulina has the highest protein and beta-carotene of all the green superfoods.Spirulina also has Gamma Linolenic Acid,Spirulina is a great foodstuff!I personally like the taste of chlorella better,the powder from now foods.The Yaeyama chlorella is a milder tasteing strain.The powders are the best way to get algae into your diet.The best prices I have found are at iherb.com.Be wise be green be healthy!!!