The light fixture is 75 watts. Only half of the lights turn on and they run at 20%. There is ~7 watts being used. I think the grouper will be fine.
I wish I could like this post more then once. It looks exactly like a transitioning blue spotted grouper. It still has the yellow fins but the body is starting to change color and get the blue spots. The fish store got another one in last week and I was able to get a good picture. This is exactly how mine looks.
Groupers come from bright places and sometimes they hang out in dark areas such as caves. Sometimes you will see them in shallow open water with the sun beating down on them. I have seen this with my aquarium groupers and seen it while diving. I provided my grouper with many places to hide such as a few statues and macro algae. He will stay in the statue most of the time with his head popping out. The same way I see Cephalopholis act in the wild.
You want to talk about creating a stressful environment. Complain to the guy who things it is OK to keep a v tail grouper in a 55 gallon tank. That is unethical. I guess people of different views on what is ethical.
The guy who is suggesting a 55 gallon for a v tail grouper is the same guy who stated that I should remove my Buddha statues which the grouper likes to hang out in. Then replace them with broken flower pots which do not provide nearly the cover, sense of security and protection from light just so he has fewer places of refuge and has a hard time hiding. I try to give my fish the optimal most stress free environment I can. If the fish feels more secure and less stress in a statue I am happy for the fish. Telling me to take away my pets shelter and area were he feels safe just so I can get a better picture of it is cruel and insensitive.