Years ago I kept a young perch in an aquarium with a vision to see how much, and how quickly, it would grow. I borrowed a set of scales from my science teacher at school and was all prepared to make scientific history.
Unfortunately I had underestimated the greed of perch and came home after school to find my perch had decided to take charge of the situation. It had attempted to swallow one of the other inhabitants in the tank – a fish about two-thirds the size of the perch. The perch swum around for the rest of the day with the other unfortunate fish’s tail poking out its mouth. Next morning the perch was also dead.
I kept perch in tanks again, back then, but never explored their growth patterns. What would’ve been useful then is Perch Dissection in Mr. Tippett’s Biology Class. This excellent set of photos clearly shows the inner workings of a fish.