To my knowledge epsom doesn’t do much besides help to calm stress.
If metroplex + focus is available, that can work.
Epsom salt helps against spironuclues vortens, the intestinal protozoan flagellate parasite that causes hexamita, showing symptoms like white stringy poo or hole in the head or lateral line erosion, or any combination. Using epsom salt and metronidazole, is generally the 1, 2 punch to knock out spironucleus vortens. It's why NLS hex shield as invented (epsom salt + metro).
Here's the sticky on S. vortens and epsom salt
Treating Hexamita aka Spironucleus
Treating Hexamita aka Spironucleus with Epsom Salt Solution This is a rather safe way to treat any newly imported fish, as a prophylactic, just as one would use a de-wormer. It's not only an extremely cheap way to treat fish, the active ingredients are readily available world-wide, and it's...