If it is still eating and/or will eat it, you can start by using antiobiotic food pellets. They sell them at PetSmart, I think by Jungle labs. You may also try to use erythromycin and keep the tank at around 80 degrees. It will be dificult to know the cause of the symptoms but it sounds like a bacterial infection that has reached septicemia stage. Have you had this fish for a while? Has it recently been in any altercations with tank mates?
You may also want to do a search for Apisto specific diseases.
Good Luck, when infection reaches this stage it is very dificult to cure.
You may also want to do a search for Apisto specific diseases.
Good Luck, when infection reaches this stage it is very dificult to cure.