First off, you say you have a powerful LED
........ What kind/brand?? Just to be sure.....
Phosphates & Nitrates become important tests, even for softies. Most of them can handle "dirtier" conditions, but only to a limited extent.
Calcium, Alkalinity, & Magnesium aren't as important, but testing would still be advisable just to be sure your balance is good. And, knowing the tests & parameters will help you when you move up to LPS
, which you eventually will, I can about guarantee it.
All "beginner" (and most advanced) corals are photosynthetic..... meaning they get what they need from a combination of light & dissolved nutrients in the water column. There are many that will accept food, but it's not necessary. In fact, attempting to feed corals is where many usually overfeed their system and wind up creating far greater problems with excess nutrients (phosphates) & algae.