Quote from one of you OTHER threads on the same subject "My tank is a reef tank. I used to run metal halides but switched to LED's.
For a fish only system I would use LED's or fluorescent lighting. No need for high power lighting for fish. As for LED types, there are all kinds but if for example you are planning a 2000G reef style tank, I'd budget $20,000 or more to light it properly using LED's."
You have started MANY threads on very few subjects. Some of which are locked already. This site has a search function that can answer MANY of the questions you have. If you are finding that the answer to the questions you asked doesn't match the answer you are expecting to find(which seems to be the theme in most of your threads); well then maybe you need to change what your expectations are and take some of the invaluable advice people are giving you.