Ok, Multies are not doing well. Here are the symptoms and what I've tried.

Fish show lesions with puffy white fuzz.

Severely affected adopt a head up or head down orientation in corners near surface or plants.

Complete loss of appetite.

Stringy clear and white bowel movements.

Fraying and disintegration of the tail with white edging.

Some other fins affected as well but without disintegrating.

All fish are flashing against objects in the tank sometimes very vigorously, sometimes just a brush by.

I've seen some fish spasm (mid water) like they had a horrible itch or something...

I've completed three treatments with Jungle Labs Internal Parasite Guard
(25% PWC between treatments (every other day))
Almost two weeks of treatment with Melafix and Pimafix
Almost two weeks of treatment with QuickCure.
(Just did a 40% PWC tonight)

Of eight, one male is dead, two females are dead, and one female's starting to stay near the top corner... (one female has a facial deformity but is well other than that)

I thought that it might be Hexamita because of where the lesions were (mostly near the head) but I just don't know anymore. :(

They're in a tank that was set up just for their needs and has a cycled filter with water chemistry that's very good (0,0,<5, ph7.6, 78F)

ANY help is appreciated.