Krish
RF STAFF
Watts/gallon rule is archaic, outdated and doesn't really mean much, so you're good. This is why I didn't bother to mention my Watts/gallon, in my original post.
For example, I'm running 540 watts of T5HO, with individually contoured reflectors, over a 200 gallon, 27" deep tank.
That's 2.7 watts/gallon.
I can grow SPS anywhere in my tank, including on the glass bottom.
The reason I originally asked to state watts per gal was just for the simple fact that a lot of new people like to have some general idea of what they would need. Same thing like when asking about live rock. Someone might ask how much rock would they need and they are given a general idea of lbs per gal. Doesn't mean it is gospel because there are many things you could factor in like how dense the rock is as 10 lbs of one type of rock could provide more biological filtration than 20 lbs of another and so it is the same with lighting. You could have a 20 gal tank 30 inches tall and another 20 gal only 10 inches tall where both will require different lighting. So it was just mentioned just to give people a general idea and nothing more.