In reefing things take time and it can take month before you see improvement with SPS stick. Sometimes they go dormant and do nothing for months and suddenly they will grow or die.
Unpredictable hobby in that regard.
In the meantime you might want to buy, borrow or steal different SPS like birdnest or Montipora and see if they grow. The idea is to build up coral mass so the tank becomes stable. Waiting for one frag will not get you there.
At the beginning you might want to get cheaper frag once a week and see how things go. Some will survive, some will not but cheaper generally means tolerant and easier to grow. Expensive means hard to keep and grow.