Hi guys really need help on one side clamped fin and sometimes flicking fins discus. Sometimes even dashed across.
It has gone through twice continual treatment of Eiho prazi gold and metro cure together treatment in the past 2 weeks yet still handful of discus remaining not eating and with the above mentioned problems.

In a 3 ft tank during medication water change has not been done for 2 weeks, ammonia and nitrate is at normal level without exceeding 0.25 temperature at 31C
However after 2 weeks 100 percent water change some of the discus still not eating and some still with one side clamped fin.

Have been google around some suggest salt, Waterlife sterazin, Furan etc. everyone suggest differently so which is which.
I dont wish my discus to go through unnescessary medication.
Discus about 2.5-3 inches running on eheim 2217

Those with experience on likewise discus problems please help