lots of small water changes. maybe 20% or so daily. try an antibacterial food and shelled peas for a week. you can also add epsom salt to the water, 2tbs/1g. just make sure you compensate for water evaporation when adding salt to the new water as salt doesnt evaporate.
if you have already fed antibacterial food (not sure what meds you gave for 4 weeks) and he is still bent(???) then its like FW TB (no need to freak) and its incurable. if THATS the case, euthanize. use clove oil, 5 drops per ounce of tank water. shake well, add fish. when he stops moving, put him in the freezer.
Chris- Husband, 04/30/77
Cailyn- Daughter, 07/05/99
Jeffrey- Son, 03/24/06
Alex- Son, 03/25/09
Mister- Black LabX, M, 08/06(?)
The Shadow Stalker- Gray Tux DSH, M, 04/04
The Mighty Hunter- Black Tux DSH, M, 04/04
Baby Girl- Tabby DMH, F, 12/03(?)
Frances- Tortie, DSH, F, 2007(?)