Hi Emily,
The owner of NLS (Pablo Tepoot) has a 2000 gallon SW show tank in his home (he's a SW keeper first & foremost) which contains species such as; Butterfly Fish, Parrot Fish, Philippine Regal Angels, Majestic Angels, Rock Beauty, Moorish Idol, Clown Tang, and Achilles Tang, and they all eat New Life Spectrum exclusively.
Perhaps this will explain things better:
http://www.cichlid-forum.com/article...e_spectrum.php
There are lots of myths & misconceptions with regards to fish nutrition, and there are many manufacturers of food who sell their products with slick marketing hype. You won't find that with NLS.
Pablo has been raising & breeding fish for 30+ years, is the author of 4 books, and has the largest African cichlid farm in North America. His food, as well as his fish are shipped world-wide, and with a min order of 2K for his fish, you know he's got to be doing something right.