It's also used for a coral dip if you mix it strong... I used it, it's going to e age or the tank, I don't expect it to just downright kill the ick immediately, but it's got aloe and natural tea stuff in it...? It smells interesting, and hopefully it will coat the fish and heal their ick sores and stuff at least so they can fight it off fully. Active ingredient is 1.25% melaleuca. On the back the description says:
"A safe, all natural way to treat bacterial infestions in saltwater fish and corals. Use to treat open, red sores, and wounds, fin and tail rot, eye cloud, pop eye, body slime, and mouth fungus on fish. Melafix marine is used in commercial coral farms to control bacterial infections, tissue degredation, and for the removal of parasitis flat worms in wild corals...treating won't harm anything or screw up your biological filtration."