Watts vs Watts

Ok Im having a hard time understanding something hopefully someone who knows something about it can clarify this for me. I understand that lets just say for example you have a reef and you dont want to be limited as to what you can keep theres a formula that is wattage per gallon dont know the actual numbers off the top of my head and I understand that it may vary a bit depending on the depth of your tank but for the most part more wattage the better without over doing it dont want to cook your coral. But what Im trying to get at is that I have a PC lighting 2 white bulbs 2 blue bulbs 96w each bulb which equals 384w. But Im told that t5ho that are 4 bulbs at 54w each which equals 216w is better than my power compacts why and how is that?

 

The watts per gallon was good for T8 and T12 bulbs.

The reason the T5HO is better than the PC bulbs is better quality bulbs, ballasts for T5HO are better engineered and more effective and efficient and the reflectors. A single bulb reflector is far more efficient at reflecting photons into the tank because photon restrike, hitting the bulb, can be more effectively eliminated than with the double bulb design.