above.. and its' been a few days so I'll put in my 2cts.. I usually address poor eaters/refusers with live foods... not just minnows, try nightcrawlers, and live blackworms as well. crickets on the surface... don't have experiance w/ that species in particular but throw anything he might look at as food to see what he does. ... If these are all refused... I try and leave a small group of live fish/ or offer worms every other day... ( anything that won't compromise the system) Then I prazi-pro/de-worm... I've found many fish to stop eating because they've picked up IP's... Even if there is no evidence of it.. at this point... it's better to do something then nothing ( no your not the only one who trys to save a poor healthed fish 
) I'm not sure why but even in fish that don't blow any worms or otherwise indicate they had IP's will often start eating after a day or 2 w/ prazi treatment ime. Liquid Vitamins.... Are usually my last resort. Since fish absorb things thew their gills ect from the water around them... opposed to force feeding I utilize liquid vits/garlic. When working with weak fish I also ALWAYS start w/ a 1/2 dos of any med/treatment/ect and go from there... gradually upping the amount to where I want/need it. "Bombing" a fish thats already weak/compromised immune system imo is no smarter then doing it when I'm sick.. though we metabolize differently ect.. Shock the system as little as possible.... TBH I"ve never resorted to force feeding any animal... the negatives far out-weight the positives in the vast majority of cases... it's very easy to do damage to the animal.
I'm sure you've already checked.. but rule out water chemistry complications. Did he go threw a KH/GH/PH shock? those can be a long time in recovering from as well if the fish is lucky enough to survive it. Ammonia burn on the gills might also keep an otherwise heathy fish from eating until it heals up.
GL and hope he's doing alright!
) I'm not sure why but even in fish that don't blow any worms or otherwise indicate they had IP's will often start eating after a day or 2 w/ prazi treatment ime. Liquid Vitamins.... Are usually my last resort. Since fish absorb things thew their gills ect from the water around them... opposed to force feeding I utilize liquid vits/garlic. When working with weak fish I also ALWAYS start w/ a 1/2 dos of any med/treatment/ect and go from there... gradually upping the amount to where I want/need it. "Bombing" a fish thats already weak/compromised immune system imo is no smarter then doing it when I'm sick.. though we metabolize differently ect.. Shock the system as little as possible.... TBH I"ve never resorted to force feeding any animal... the negatives far out-weight the positives in the vast majority of cases... it's very easy to do damage to the animal.I'm sure you've already checked.. but rule out water chemistry complications. Did he go threw a KH/GH/PH shock? those can be a long time in recovering from as well if the fish is lucky enough to survive it. Ammonia burn on the gills might also keep an otherwise heathy fish from eating until it heals up.
GL and hope he's doing alright!
