Aussie tusk unable to catch food

[Realposition]

have a Aussie Harlequin tusk who ive had for about 8 months, always been a pig and ate anything i threw in tank. recently it almost seems like he is loosing his vision, he tries to catch food when i feed but just cant seem to get it, if it settles on the bottom hes able to suck it up but thats it. All other fish are eating and acting normally, no aggression issues that i have seen. I QT all my fish with copper and prazi pro

tank is 6' 150g with a 150g sump and a 40g frag tank. has been running for a little over a year without issue.
Salinity 1.026
ammonia 0
nitrite 0
nitrate 1

has anyone experienced this? ive never had a fish that couldnt catch food it was interested in eating. thanks

 

[HumbleFish]

I've had this happen to fish going blind several times. You either have to start target feeding or figure out some other method to provide "special care"; or the fish slowly starves to death. This also applies to fish suffering from swim bladder disorder.