There isn't a truly reef-safe method that will always work unfortunately. Methods that are known to kill marine ich (hyposalinity and copper) will kill your reef. Your choices basically come down to let them live with it and hope it doesn't kill off your livestock (many fish can live with it for a long time but they are often suffering even if they seem otherwise healthy) or remove the fish, treat them and leave the display empty for 8 weeks. Tough choices. Cleaner wrasses and shrimps will not cure it and neither will raising the temp, garlic and other saltwater myths. The only true cures are hypo and copper and leaving the display without fish for 8 weeks. Good luck with it! Keep us posted.
There is no good method. I battled it a long time ago. ended up going the Hyposalinity route in my display since I had no corals at the time. that is the only sure fire way in my opinion. saltwater ich is an evil protozoan.
UV sterilizer makes a huge difference. I have a blue tang in my tank and unfortunately it is starving to death because it won't eat, but not one sign of ich.
Yes. UV can make a difference. I can attest to that in helping with water borne pathogens like crypto. I personally run about 75 watts on my system. The key is to have good contact time. Slower flow and lots of wattage. If you do go that route, buy double the tank rating. Otherwise you won't get effective kill. Also a UV is non selective so even good things in water are killed.
I have used no ick marine successfully with coral 2 times and had no issues using it. Had a friend just use it and have success as well. Foster and smith carries it. It's pricey but has and does work. No issues with any corals polps, Lps or Sps from it