Fish seems skinny, what to do?

didn't notice about the skinniness, like i said i'm pretty new so don't really know the difference of a skinny fish, except for now i do, and a nice and healthy fish. So she good have looked a little skinny then. And eating habits, have been a ok. After i acclimated them i fed them a tiny little bit, they didn't go for the food, i also didn't have garlic at the time and figured they were just getting used to everything. I fed them the day after, still no garlic at the time but they went for the food a little bit. Wednesday i went and got some garlic and they ate, within a few minutes. And yesterday and today i noticed she wasn't active and swimming near the bottom. And tonight i was really concerned and looked at her and noticed her bones, sticking out. And tonight i fed them to try to fatten her up some, and let her gain more strength to swim in the current.

 

well i feed my fish half a cube (maybe a little less), everyday. the are the brad emerald. My parameters have always been good..

 

so it's been a few minutes after they ate, she is the most active that i have seen her since the past day or so.

 

everything loves some fresh shrimp, maybe they dont like what your feedin em.