Some folks recommend a 6 line wrasse, I didn't want to house a 6 line so I took the flatworm exit route. I just treated with flatworm exit and experianced some issues. Have enough water ready to do your WC and have your carbon ready. Make sure you have enough additional water for an emergency wc as well. Watch your ammonia! The ammonia spiked a couple of hours after treatment for us. Vacuum as many out as possible before you treat, they become toxic when they die. Recommend having some Prime on hand as well as methylene blue for potential ammonia burn.
If you want to see what I just went through follow the link. Other folks have used it with no issues, this is probably one of the exceptions.
https://www.reef2reef.com/threads/clown-is-crashing.476277/page-3#post-5237811