I am a proud owner of two oscars, one red and the other a tiger. To start off all oscars pretty much grow at the same rate, fast until about 4-5 inches, then it'll go a bit slower. Their personalities range, but develope from the same aspect that they all share... they are very aggresive creatures, which gives them the confidence to get to know their owners. Everytime I pass their tank.. they shoot up wanting to be fed. I usually have to rop it quick because these guys, like all oscars, get excited for food and try to get it before you want them to. One of my oscars accidently trie to swollow my pinky when I was feeding (lucky for me they don't have teeth!). The REALLY important things to have for oscars is a fairly decent sized aquarium (55+ for one oscar, 75+ for a pair). But remember this.. the bigger the aquarium the more diluted any filth in there gets (like uneaten food). This goes hand in hand with filtration, which oscars needs the best of... You need pretty decent filtration to keep these guys happy and heathly. Unfortunately these guys are prone to HITH (Hole in the head disease) when aquariums are too small, causing the water to be easily contaminated (or poor filtartion will also cause this as well).
If you want a fish that won't grow so big but eat from your fingers.. well I would search cichlids and aggressive. I can;t think of any off the top of my head, but I think there are some... it also depends what you consider not too big. Good luck
