Salifert flatworm exit. Pick as many out as you can first, have fresh carbon on hand, dose FWE, pick out all of the dying ones that you can see and be prepared to do a massive water change afterward, then put in new carbon. The FWE is safe to use but the dead worms release a toxin in your tank and can kill everything in it if you don't get the dead ones out.
Or if you know anyone with a blue velvet nudibranch, borrow that first, then use FWE to get any left behind. Wrasses are supposedly hit or miss.
Tankyou. I am leaving for St. Thomas in a week. I will suck as many as I can out and do a water change. I'll wait to do the flatworm exit when I get back from vacation.
I would say velvet nudibranch first, but you will have to get rid of him unless you want to add more flatworms for him to survive. After that use FWE or just use FWE after manually removing as many worms as you can.
It is worth a shot. Also, with the velvet nudi, it might be a pain to get rid of as there probably not that many people that want to intentionally introduce flatworms into their tank.