They don't "require" feeding. They may benefit from it but not a guarantee you'll visually see any improvement. They will grow and thrive with just stable parameters and light. I have a red flowerpot I never direct feed it, just gets t5 lights, and whatever fish poo (there is a lot from my tangs) and/or particles that are floating around the tank.
But if you wanna direct feed with a syringe, powerheads off, then have at it. Doesn't need to be done more than once or twice a week with very small amounts in order not to promote cyano. I would highly recommend reef roids.