Fish in the tank

I recently picked up a new fully manual lens, but have not felt comfortable taking pictures on it due to my inexperience.

I decided to spend some time and capture pics of my rapidly moving fish. My focus was to practice with the lens, so some of the pics have glare and not properly lit, but that was not my focus. I wanted to get used to the functions of my lens.

I had it set in the "P" setting with the ISO set at 1600, the focus set at spot and the camera set up at vivid.