I've had some torches...and unfortunately they've gone through a similar process in what I see yours doing.
Once the tissue starts to recede on the stems, that's not a good sign. The coral is looking for one of a few things. More light, more calcium, or more food. Food part can be easy. Take a 2 litre bottle top (cut it) and force it into the sand around the coral (just to keep the fishies out). You can put cyclopeez into the top and let it float around it...if it takes it, you're good...if not it's something else. Don't leave the bottle on there for more than 30 minutes. Lighting is tricky...I've never had issues with VHO or Halide...I can't tell what you have on yours, hopefully sufficient. Obviously check your calc levels or get a water change in to raise it.
No need to worry about purple up...you'll get the algae you're looking for naturally with time.
Proud owner of 1 Turbo and 2 Superchargers