Ammonia problem.

[XROCKSTARX]

I’m having an ammonia problem in my tank. I feed Mysis shrimp and maybe I’m feeding too much cuz some floats to the bottom. I only feed once a day and I did a water change yesterday. But my ammonia still is kinda high? It’s at .50 and I’m unsure of how to get rid of it. I added prime but how do I keep it down?

 

[Spare time]

How old is the tank? How was it cycled? What test kit (and show a picture of the result if possible)? Is there any nitrite present?