medicated with kanaplex/focus for 2 weeks with no improvement. Advice?

This tank has been fed mysis shrimp mixed with kanaplex/focus for around 2 weeks now. There have been no significant changes in these ulcers. Could I please get some advice on next treatment? My main issue is i do not live at home for college so can only visit tanks on weekends & am the only person who does water changes which rules out a handful of medications.

current water parameters: 0 ammonia, 0 nitrites, .15 nitrates