“Pop” seems to be the word used to describe any visual characteristic that you wish your coral had. There is no basis in coral health.
The idea seems to be magnified by looking at DSLR camera photos. I’ll paraphrase an actual thread on the topic:
Zowie! Zowie! LED’s will pop your corals!
The only way I can show you is through a DSLR camera.
Worth linking in our “DSLR Camera” article about now.
Supposedly the term “pop” has some actual artistic meaning in unrelated industries.